SE539928C2 - Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle - Google Patents

Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle Download PDF

Info

Publication number
SE539928C2
SE539928C2 SE1650747A SE1650747A SE539928C2 SE 539928 C2 SE539928 C2 SE 539928C2 SE 1650747 A SE1650747 A SE 1650747A SE 1650747 A SE1650747 A SE 1650747A SE 539928 C2 SE539928 C2 SE 539928C2
Authority
SE
Sweden
Prior art keywords
pressure
air
circuits
vehicle
sensors
Prior art date
Application number
SE1650747A
Other languages
Swedish (sv)
Other versions
SE1650747A1 (en
Inventor
Jeddi Tehrani Hossein
VADASZ Richard
Original Assignee
Scania Cv Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Scania Cv Ab filed Critical Scania Cv Ab
Priority to SE1650747A priority Critical patent/SE539928C2/en
Priority to DE102017004896.7A priority patent/DE102017004896B4/en
Publication of SE1650747A1 publication Critical patent/SE1650747A1/en
Publication of SE539928C2 publication Critical patent/SE539928C2/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/66—Electrical control in fluid-pressure brake systems
    • B60T13/662—Electrical control in fluid-pressure brake systems characterised by specified functions of the control system components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
    • B60T17/18—Safety devices; Monitoring
    • B60T17/22—Devices for monitoring or checking brake systems; Signal devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
    • B60T13/26—Compressed-air systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/66—Electrical control in fluid-pressure brake systems
    • B60T13/68—Electrical control in fluid-pressure brake systems by electrically-controlled valves
    • B60T13/683—Electrical control in fluid-pressure brake systems by electrically-controlled valves in pneumatic systems or parts thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
    • B60T17/02—Arrangements of pumps or compressors, or control devices therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/88—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration with failure responsive means, i.e. means for detecting and indicating faulty operation of the speed responsive control means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
    • B60W10/30—Conjoint control of vehicle sub-units of different type or different function including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Valves And Accessory Devices For Braking Systems (AREA)

Abstract

The present invention relates to a method for diagnosing functionality of pressure sensors (72, 74, 76, 78) for detecting pressure level in air circuits (C1, C2, C3, C4, C5, C6) for supplying compressed air for certain systems of a vehicle comprising brake systems of the vehicle. The distribution of pressurized air to said air circuits is controlled by means of an air processing system (I) such that below a certain lower pressure level said air circuits (C1, C2, C3, C4, C5, C6) are separated from each other, and within a pressure range above said certain lower pressure level said air circuits (C1, C2, C3, C4, C5, C6) are in fluid connection with each other. The method comprises the steps of: controlling the pressure to a pressure within said pressure range; determining the pressure detected by the respective pressure sensor (72, 74, 76, 78); and; comparing the thus determined pressures detected by the respective sensor for diagnosing the functionality of said pressure sensors.The present invention also relates to a system for diagnosing functionality of pressure sensors for detecting pressure level in air circuits for supplying compressed air for certain systems of a vehicle. The present invention also relates to a vehicle. The present invention also relates to a computer program and a computer program product.

Description

I\/IETHOD AND SYSTEM FOR DIAGNOSING FUNCTIONALITY OFPRESSURE SENSORS IN AIR CIRCUITS OF A VEHICLE TECHNICAL FIELD The invention relates to a method for diagnosing functionality of pressuresensors for detecting pressure level in air circuits for supplying compressed airfor certain systems of a vehicle according to the preamble of claim 1. Theinvention also relates to a system for diagnosing functionality of pressuresensors for detecting pressure level in air circuits for supplying compressed airfor certain systems of a vehicle. The invention also relates to a vehicle. Theinvention in addition relates to a computer program and a computer program product.
BACKGROUND ART Vehicles, for example heavy vehicles such as trucks, are provided with an airprocessing system for controlling and distributing compressed air to certainsystems of the vehicle comprising safety critical systems such as brakesystems of the vehicle with an air circuit for rear service brakes, an air circuitfor front service brakes and an air circuit for parking brake, and the powertrainsystem with an air circuit for the powertrain. ln order to provide information to the air processing system about the pressurein such safety critical air circuits pressure sensors are arranged for detectingpressure level in air circuits such as the air circuit for rear service brakes, theair circuit for front service brakes, the air circuit for parking brake, and the aircircuit for the powertrain.
Thus, it is important that the pressure sensors functions correctly and provide an accurate pressure in order for the air processing system to decide if the Compressor should be active or not. Failure of a pressure sensor would resultin incorrect pressure information to the air processing system. lt is thereforedesired to perform diagnostics of the pressure sensors.
Different ways of diagnosing of pressure sensors are known. FF¶2945321 forexample discloses diagnosing of pressure sensors in a supercharged sparkignition engine of a vehicle, the diagnosing involving comparing pressurevalues provided by three pressure sensors when engine is stopped.
There is however a need to provide a method particularly suitable fordiagnosing of functionality of pressure sensors for detecting pressure level inair circuits for supplying compressed air for certain systems of a vehicle.
OBJECTS OF THE INVENTION An object of the present invention is to provide a method for diagnosingfunctionality of pressure sensors for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle which is easy andprovides a reliable diagnose.
Another object of the present invention is to provide a system for diagnosingfunctionality of pressure sensors for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle which is easy andprovides a reliable diagnose.
SUMMARY OF THE INVENTION These and other objects, apparent from the following description, are achievedby a method, a system, a vehicle, a computer program and a computerprogram product as set out in the appended independent claims. Preferred embodiments of the method and the system are defined in appendeddependent claims.
Specifically an object of the invention is achieved by a method for diagnosingfunctionality of at least two pressure sensors used for detecting pressure levelin at least two air circuits for supplying compressed air to systems of a vehicle,said systems comprising brake systems of the vehicle. The distribution ofpressurized air to said air circuits is controlled by means of an air processingsystem, wherein the air processing system is adapted to separate said aircircuits from each other so that they are fluidly disconnected when the airpressure is below a first pressure level, and wherein the air processing system(I) is adapted to connect said air circuits to each other so that they are in fluidconnection with each other when the air pressure is within a pressure rangeabove said first pressure level. The method comprises the steps of: controllingthe pressure to a pressure within said pressure range; determining thepressure detected by each pressure sensor; comparing the thus determinedpressures detected by each pressure sensor; and based on the comparison ofthe determined sensor pressures performing a diagnosing of the functionality of said pressure sensors.
By thus comparing the determined pressure of the pressure sensors within thepressure range in which the air circuits are in fluid communication with eachother an easy and reliable way of diagnosing the pressure sensors is obtainedin that the pressure of the different pressure sensors should be the same withinthat pressure range and if not, malfunction of the differing pressure sensor canbe determined.
The air processing system comprises a multi circuit protection valve fordistribution to air systems of the vehicle for controlling the air circuits such thatthey are in fluid connection with each other within said certain pressure range above the lower pressure level.
According to an embodiment the method comprises the step of determining amalfunction of a pressure sensor if the determined pressure detected by thatpressure sensor differs more than a pre-determined pressure value comparedto the other pressure sensors. Hereby a possible malfunction of a pressuresensor may be easily and reliably determined.
According to an embodiment the method comprises the step of during or a pre-determined time period changing pressure to another pressure within saidpressure range. Changing the pressure to another pressure within saidpressure range may comprise lowering the pressure which may be performedby means of a valve such as a purge valve. Changing the pressure to anotherpressure within said pressure range may comprise increasing the pressurewhich may be performed by means of a drive member, e.g. the internalcombustion engine of the vehicle, for driving the compressor of the airprocessing system. Hereby an even more accurate diagnose is obtained in that the pressure sensors are diagnosed at another pressure level.
According to an embodiment of the method the step of during a pre-determinedtime period changing pressure to another pressure within said pressure rangecomprises lowering the pressure by means of exhausting air from said air circuits. Hereby an efficient way of the changing the pressure is obtained.
According to an embodiment the method comprises the step of determiningthe amount of air exhausted from said circuits during said time period forlowering the pressure; determining an expected pressure reduction resultingfrom the exhaustion of air; comparing the expected pressure reduction withthe pressure reduction detected by the respective pressure sensors; andperforming a diagnosing of the functionality of said pressure sensors alsobased on the comparison between the expected pressure reduction and thedetected pressure reduction. By thus determining the amount of air exhaustedfrom said circuits when lowering the pressure to another pressure within thepressure range where the circuits are in fluid communication the expected pressure decrease may be determined based upon the amount of exhausted air during that time period such that an even more accurate diagnosing of the pressure sensors is obtained.
Specifically an object of the invention is achieved by a system for diagnosingfunctionality of at least two pressure sensors used for detecting pressure levelin at least two air circuits supplying compressed air to systems of a vehicle,said systems comprising brake systems of the vehicle. The distribution ofpressurized air to said air circuits is controlled by means of an air processingsystem, wherein the air processing system is adapted to separate said aircircuits from each other so that they are fluidly disconnected when the airpressure is below a first pressure level, and wherein the air processing system(I) is adapted to connect said air circuits to each other so that they are in fluidconnection with each other when the air pressure is within a pressure rangeabove said first pressure level. The system comprises means for controllingthe pressure to a pressure within said pressure range; means for determiningthe pressure detected by each pressure sensor; means for comparing the thusdetermined pressures detected by each pressure sensor; and means forperforming a diagnosing of the functionality of said pressure sensors based onthe comparison of the determined sensor pressures.
According to an embodiment the system comprises means for determining amalfunction of a pressure sensor if the determined pressure detected by thatpressure sensor differs more than a pre-determined pressure value compared to the other pressure sensors.
According to an embodiment the system comprises means for during a pre-determined time period changing pressure to another pressure within said pressure range.
According to an embodiment of the system the means for during a pre-determined time period changing pressure to another pressure within saidpressure range comprises means for lowering the pressure by means of exhausting air from said air circuits.
According to an embodiment the system comprises means for determining theamount of air exhausted from said circuits during said time period for Ioweringthe pressure; means for determining an expected pressure reduction resultingfrom the exhaustion of air; means for comparing the expected pressurereduction with the pressure reduction detected by the respective pressuresensors; and means for performing a diagnosing of the functionality of saidpressure sensors also based on the comparison between the expectedpressure reduction and the detected pressure reduction.
The system according to the invention has the advantages according to thecorresponding method claims.
Specifically an object of the invention is achieved by a vehicle comprising asystem according to the invention.
Specifically an object of the invention is achieved by a computer program fordiagnosing functionality of pressure sensors for detecting pressure level in aircircuits for supplying compressed air for certain systems of a vehicle, saidcomputer program comprising program code which, when run on an electroniccontrol unit or another computer connected to the electronic control unit,causes the electronic control unit to perform the method according to the invenfion.
Specifically an object of the invention is achieved by a computer programproduct comprising a digital storage medium storing the computer program according to the invention.
BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention reference is made to thefollowing detailed description when read in conjunction with the accompanyingdrawings, wherein like reference characters refer to like parts throughout the several views, and in which: Fig. 1 schematically illustrates a side view of a vehicle according to the present invenfion; Fig. 2 schematically illustrates an air processing system of a vehicle according to an embodiment of the present invention; Fig. 3a schematically illustrates pressure levels over time for air circuits of the air processing system in fig. 2; Fig. 3b schematically illustrates control of the pressure levels of the air circuitsof the air processing system in fig. 2 within a pressure range where the air circuits are in fluid communication with each other; Fig. 4 schematically illustrates a system for diagnosing functionality ofpressure sensors for detecting pressure level in air circuits for supplyingcompressed air for certain systems of a vehicle comprising brake systems ofthe vehicle according to an embodiment of the present invention; Fig. 5 schematically illustrates a block diagram of a method for diagnosingfunctionality of pressure sensors for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle comprising brakesystems of the vehicle according to an embodiment of the present invention;and Fig. 6 schematically illustrates a computer according to an embodiment of the present invention.
DETAILED DESCRIPTION Hereinafter the term “link” refers to a communication link which may be aphysical connector, such as an optoelectronic communication wire, or a non-physical connector such as a wireless connection, for example a radio or microwave link.
Fig. 1 schematically illustrates a side view of a vehicle 1 according to thepresent invention. The exemplified vehicle 1 is a heavy vehicle in the shape ofa truck. The vehicle according to the present invention could be any vehiclesuch as a bus or a car. The vehicle comprises a system for diagnosingfunctionality of pressure sensors for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle comprising brakesystems of the vehicle.
Fig. 2 schematically illustrates an air processing system I of a vehicle. The airprocessing system I is configured to receive compressed air A distributed bymeans of a compressor 10 operated by a drive member, e.g. a combustion engine of the vehicle, not shown.
The air processing system I comprises an air dryer 20 for drying and filteringthe air from particles from e.g. oil from the engine. The air dryer 20 comprisesa desiccant cartridge 22 and a support member 24. The support member 24 isaccording to a variant called air dryer body. The support member 24 isconnected to a purge valve 30 configured to exhaust moist collected by thefilter of the air dryer. The purge valve 30 is used during regeneration whendried air A1 is returned through the desiccant cartridge 22 to dry, wherein theair is discharged through the purge valve 30. The purge valve 30 may be usedto reduce the pressure in the air processing system I by exhausting air.
The air processing system I comprises a multi circuit protection valve 40connected to the air dryer 20. The multi circuit protection valve 40 is configuredto distribute the dried air from the air dryer 20 via a distribution block 50 tocircuits G1, G2, G3, G4, G5, G6 of different systems of the vehicle. ln the air processing system I according to this embodiment air is configuredto be distributed to an air circuit G1 for the for front service brakes, an air circuitG2 for rear service brakes, an air circuit G3 for parking brake, an air circuit G4for the vehicle cabin, an air circuit G5 for the air suspension system and an aircircuit G6 for the powertrain. One or more of the air circuits may be connected to air reservoir tanks. Here the air circuit G1 is connected to a reservoir tankF11, the air circuit G2 is connected to a reservoir tank Fï2, the air circuit G3 isconnected to a reservoir tank Fï3, the air circuit G4 is connected to a reservoirtank R4, the air circuit G5 is connected to a reservoir tank Fï5, and the air circuitG6 is connected to a reservoir tank R6. ln order to provide information to the air processing system l about thepressure in safety critical air circuits G1, G2, G3, G6 pressure sensors 72, 74,76, 78 are arranged for detecting pressure level in those air circuits. A pressuresensor 72 is arranged to detect the pressure in the air circuit G1 for frontservice brakes. A pressure sensor 74 is arranged to detect the pressure in theair circuit G2 for rear service brakes. A pressure sensor 76 is arranged todetect the pressure in the air circuit G3 for parking brake. A pressure sensor78 is arranged to detect the pressure in the air circuit G6 for the powertrain.
The distribution of pressurized air to said air circuits G1, G2, G3, G4, G5, G6 iscontrolled by means of the air processing system l such that below a certainlower pressure level said air circuits G1, G2, G3, G4, G5, G6 are separatedfrom each other, and within a pressure range above said certain lowerpressure level said air circuits G1, G2, G3, G4, G5, G6 are in fluid connectionwith each other. The multi circuit protection valve is arranged to perform saidcontrol of distribution of air to said air circuits G1 , G2, G3, G4, G5, G6 such thatbelow a certain lower pressure level said air circuits G1, G2, G3, G4, G5, G6are separated from each other, and within a pressure range above said certainlower pressure level said air circuits G1, G2, G3, G4, G5, G6 are in fluidconnection with each other.
According to an embodiment there is a certain allowable highest pressure levelin the air circuit G1 for the for front service brakes, the air circuit G2 for rearservice brakes, and the air circuit G5 for the air suspension system. The certainallowable highest pressure level in the air circuit G1 for the for front servicebrakes, the air circuit G2 for rear service brakes, and the air circuit G5 for the air suspension system is higher than a certain allowable highest pressure level in the air circuit G3 for parking brake, the air circuit G4 for the vehicle cabinand the air circuit G6 for the powertrain. The allowable highest pressure levelin the respective air circuit is regulated by a pressure relief valve unit for therespective air circuit. Thus, within the pressure range above the lower pressurein which the air circuits are separated from each other and up to the highestallowable pressure level for the air circuits G3, G4, G6 the pressure level in allair circuits should be the same. Fig. 3a illustrates those different pressurelevels for the air circuits.
The air processing system comprises an electronic control unit 60 forcontrolling and determining the air pressure. The electronic control unit 60 isoperably connected to the pressure sensors 72, 74, 76, 78 via links. Theelectronic control unit 60 is arranged to receive signals representing data forpressure determined by said pressure sensors in the air circuits G1, G2, G3,G6.
The electronic control unit 60 is according to an embodiment operablyconnected to the purge valve 30. The electronic control unit 60 is arranged tocontrol the purge valve 30 for exhausting air for lowering the pressure in the air circuits.
The electronic control unit 60 is according to an embodiment operablyconnected to the multi circuit protection valve 40.
The compressed air A from the compressor 10 is thus introduced into the airdryer 20 and is led through the desiccant cartridge 22 into the support member24. The dried air A1 is then led to the distribution block 50 via the multi circuitprotection valve 40 for distribution to air systems of the vehicle. ln order to diagnose the functionality of pressure sensors for detectingpressure level in the air circuits G1, G2, G3, G4, G5, G6 the pressure iscontrolled to a pressure within said pressure range, wherein the pressuredetected by the respective pressure sensor 72, 74, 76, 78 is compared. lf thepressure determined by the respective pressure sensor 72, 74, 76, 78 is 11 essentially the same the pressure sensors are diagnosed as likely to function.lf the pressure detected by a pressure sensor differs to a certain degreecompared to the other pressure sensors a possible malfunction of that pressure sensor is determined. ln order to further diagnose the functionality of pressure sensors for detectingpressure level in the air circuits G1, G2, G3, G4, G5, G6 the pressure ischanged, e.g. lowered by exhausting air by means of the purge valve 30, toanother pressure within said pressure range. Fig. 3b discloses control of the pressure and lowering of the pressure within said pressure range.
Fig. 3a schematically illustrates pressure levels over time for air circuits of the air processing system in fig. 2.
As described above with reference to fig. 2 the distribution of pressurized airto said air circuits G1, G2, G3, G4, G5, G6 is controlled by means of the airprocessing system l such that below a certain lower pressure level L3 said aircircuits G1, G2, G3, G4, G5, G6 are separated from each other as illustrated infig. 3a. The certain lower pressure level L3 could be any suitable pressure leveland is according to an embodiment in the range of about 4 bars. ln fig. 3a the certain allowable highest pressure level in the air circuit G1 forthe for front service brakes, the air circuit G2 for rear service brakes, and theair circuit G5 for the air suspension system is at a certain higher pressure levelL1. This higher pressure level L1 could be any suitable pressure level for thosecircuits G1, G2, G5 and is according to an embodiment in the range of about12 bars. The certain allowable highest pressure level L2 in the air circuit G3 forparking brake, the air circuit G4 for the vehicle cabin and the air circuit G6 forthe powertrain is lower than the certain higher pressure level L1 for the aircircuit G1 for the for front service brakes, the air circuit G2 for rear service brakes, and the air circuit G5 for the air suspension system.
Thus, within the pressure range above the lower pressure L3 in which the aircircuits are separated from each other and up to the highest allowable pressure 12 level L2 for the air circuits G3, G4, G6 the pressure level in all air circuits shouldbe the same. The pressure range is thus between L3 and L2. Within thispressure range above said certain lower pressure level said air circuits G1 , G2,G3, G4, G5, G6 are in fluid connection with each other.
Fig. 3b schematically illustrates control of the pressure levels of the air circuitsof the air processing system in fig. 2 within a pressure range where the aircircuits are in fluid communication with each other for diagnosing thefunctionality of the pressure sensors 72, 74, 76, 78 of the air processing systeml in fig. 2. ln order to diagnose the functionality of pressure sensors for detectingpressure level in the air circuits G1, G2, G3, G4, G5, G6 the pressure iscontrolled from a pressure PO to a pressure P1 within said pressure range. lnfig. 3a the pressure has initially been controlled from a pressure above thepressure level L2 to a pressure which is close to the pressure level L2 andwithin the pressure range L3-L2. The pressure detected by the respectivepressure sensor at said expected pressure P2 is compared, and if the pressuredetermined by the respective pressure sensor is essentially the same thepressure sensors are diagnosed as likely to function, and if the pressuredetected by a pressure sensor differs to a certain degree compared to the otherpressure sensors a possible malfunction of that pressure sensor is determined. ln order to further diagnose the functionality of pressure sensors for detectingpressure level in the air circuits G1 , G2, G3, G4, G5, G6 the pressure is loweredduring or a certain time period T1 by exhausting air to another pressure P2within said pressure range L3-L2. Again, the pressure detected by therespective pressure sensor is compared, and if the pressure determined bythe respective pressure sensor is essentially the same the pressure sensorsare diagnosed as likely to function, and if the pressure detected by a pressuresensor differs to a certain degree compared to the other pressure sensors apossible malfunction of that pressure sensor is determined. 13 The pressure range, in fig. 3b the range between L3 and L2, has in the graph been illustrated by hashed lines.
Fig. 4 schematically illustrates a system ll for diagnosing functionality ofpressure sensors for detecting pressure level in air circuits for supplyingcompressed air for certain systems of a vehicle comprising brake systems of the vehicle according to an embodiment of the present invention.
The distribution of pressurized air to said air circuits is controlled by means ofan air processing system such that below a certain lower pressure level saidair circuits are separated from each other, and within a pressure range abovesaid certain lower pressure level said air circuits are in fluid connection witheach other. The air processing system comprises a multi circuit protectionvalve for distribution to air systems of the vehicle for controlling the air circuitssuch that they are in fluid connection with each other within said certain pressure range above the lower pressure level.
The system ll comprises an electronic control unit 100. The electronic controlunit 100 is according to an embodiment an electronic control unit of the airprocessing system. The air processing system may be any suitable airprocessing system such as the air processing system described with referenceto fig. 2.
The system ll comprises according to an embodiment means 110 fordetermining whether the pressure is within the pressure range in which saidair circuits are in fluid communication. The means 110 for determining whetherthe pressure is within the pressure range comprises means 112 fordetermining the status of the multi circuit protection valve. The means 110 fordetermining whether the pressure is within the pressure range comprisesmeans 114 for determining the current pressure. The means for determiningthe current pressure may comprise one or more of the pressure sensors to be diagnosed and/or other pressure sensors of the air processing system. 14 The system ll comprises means 120 for controlling the pressure to a pressurewithin said pressure range where said air circuits are in fluid connection with each other.
The means 120 for controlling the pressure to a pressure within said pressurerange comprises according to an embodiment the electronic control unit 100.The means 120 for controlling the pressure to a pressure within said pressurerange comprises according to an embodiment means 122 for Iowering thepressure by means of exhausting air from said air circuits. The means 122 forIowering the pressure comprises according to an embodiment a purge valvefor exhausting air from said circuits so as to reduce the air pressure. Themeans 120 for controlling the pressure to a pressure within said pressurerange comprises according to an embodiment a means 124 for increasing thepressure. The means 124 for increasing the pressure comprises according toan embodiment a drive member 124 for operating a compressor for providingcompressed air for the air circuits of the air processing system so as toincrease the air pressure. The drive member for operating the compressor isaccording to an embodiment an internal combustion engine. The drive membercould alternatively be an electric machine, e.g. an electric machine of a hybrid vehicle or electric vehicle.
The means 120 for controlling the pressure to a pressure within said pressurerange thus comprises according to an embodiment means 122, 124 for duringa certain time period changing pressure to another pressure within saidpressure range. According to an embodiment the system ll thus comprisesmeans 122, 124 for during a certain time period changing pressure to another pressure within said pressure range.
The means 122, 124 for during a certain time period changing pressure toanother pressure within said pressure range comprises according to anembodiment said means 122 for Iowering the pressure by means of exhaustingair from said air circuits. Said means may comprise said purge valve forexhausting air from said circuits so as to reduce the air pressure.
The means 122, 124 for during a certain time period changing pressure toanother pressure within said pressure range comprises according to anembodiment said drive member 124 for operating a compressor for providingcompressed air for the air circuits of the air processing system so as to increase the air pressure.
According to an embodiment the system ll comprises means 130 fordetermining the amount of air exhausted from said circuits during said timeperiod for Iowering the pressure so as to determine an expected pressuredifference. The means 130 for determining the amount of air exhausted fromsaid circuits during said time period is according to an embodiment comprisedin the electronic control unit 100. The means 130 for determining the amountof air exhausted from said circuits during said time period comprises means132 for ca|cu|ating the time period. The means 130 for determining the amountof air exhausted from said circuits during said time period comprises means 134 for determining the expected pressure drop.
The system ll comprises means 140 for determining the pressure detected bythe respective pressure sensor. The means 140 for determining the pressuredetected by the respective pressure sensor is according to an embodimentcomprised in the electronic control unit 100. The means 140 for determiningthe pressure detected by the respective pressure sensor comprises pressuresensors 142, 144, 146, 148 for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle. The pressuresensors 142, 144, 146, 148 comprises a pressure sensor 142 for detecting thepressure in the air circuit for front service brakes, a pressure sensor 144 fordetecting the pressure in the air circuit for rear service brakes, a pressuresensor 146 for detecting the pressure in the air circuit for parking brake and apressure sensor 148 for detecting the pressure in the air circuit for thepowertrain. The pressure sensors 142, 144, 146, 148 are according to anembodiment corresponding to the pressure sensors 72, 74, 76, 76 describedwith reference to fig. 2. 16 The system ll comprises means 150 for comparing the thus determinedpressures detected by the respective sensor for diagnosing the functionality ofsaid pressure sensors. The means 150 for comparing the thus determinedpressures detected by the respective sensor is according to an embodimentcomprised in the electronic control unit 100.
According to an embodiment the system ll comprises means 152 fordetermining a malfunction of a pressure sensor if the determined pressuredetected by that pressure sensor differs to a certain degree compared to the Other DFGSSUFG SGFISOFS.
The electronic control unit 100 is operably connected to the means 110 fordetermining whether the pressure is within the pressure range in which saidair circuits are in fluid communication via a link 110a. The electronic controlunit 100 is via the link 1 10a arranged to receive a signal from said means 110representing data for whether the pressure is within the pressure range in which the air circuits are in fluid communication.
The electronic control unit 100 is operably connected to the means 112 fordetermining the status of the multi circuit protection valve via a link 112a. Theelectronic control unit 100 is via the link 1 12a arranged to receive a signal fromsaid means 112 representing data for status of the multi circuit protectionvalve.
The electronic control unit 100 is operably connected to the means 114 fordetermining the current pressure via a link 114a. The electronic control unit100 is via the link 114a arranged to receive a signal from said means 114 representing data for current air pressure.
The electronic control unit 100 is operably connected to the means 120 forcontrolling the pressure to a pressure within said pressure range where saidair circuits are in fluid connection with each other via a link 120a. The electroniccontrol unit 100 is via the link 120a arranged to send a signal to said means120 representing data for current air pressure. 17 The electronic control unit 100 is operably connected to the means 120 forcontrolling the pressure to a pressure within said pressure range where saidair circuits are in fluid connection with each other via a link 120b. The electroniccontrol unit 100 is via the link 120b arranged to receive a signal from saidmeans 120 representing data for controlling the pressure to a pressure within said pressure range.
The electronic control unit 100 is operably connected to the means 122 forlowering the pressure by means of exhausting air from said air circuits via alink 122a. The electronic control unit 100 is via the link 122a arranged toreceive a signal from said means 122 representing data for lowering the pressure.
The electronic control unit 100 is operably connected to the means 124 forincreasing the pressure via a link 124a. The electronic control unit 100 is viathe link 124a arranged to receive a signal from said means 124 representing data for increasing the pressure.
The electronic control unit 100 is operably connected to the means 130 fordetermining the amount of air exhausted from said circuits during said timeperiod for lowering the pressure so as to determine an expected pressuredifference via a link 130a. The electronic control unit 100 is via the link 130aarranged to receive a signal from said means 130 representing data for amountof air exhausted from said circuits during said time period for lowering the pressure.
The electronic control unit 100 is operably connected to the means 132 forcalculating the time period via a link 132a. The electronic control unit 100 isvia the link 132a arranged to receive a signal from said means 132representing data for time period.
The electronic control unit 100 is operably connected to the means 134 fordetermining the expected pressure drop via a link 134a. The electronic control 18 unit 100 is via the link 134a arranged to receive a signal from said means 134 representing data for expected pressure drop.
The electronic control unit 100 is operably connected to the means 140 fordetermining the pressure detected by the respective pressure sensor via a link140a. The electronic control unit 100 is via the link 140a arranged to receive asignal from said means 140 representing data for pressure detected by the respective pressure sensor.
The electronic control unit 100 is operably connected to the pressure sensor142 for detecting the pressure in the air circuit for front service brakes via alink 142a. The electronic control unit 100 is via the link 142a arranged toreceive a signal from said means 142 representing data for pressure in the air circuit for front service brakes.
The electronic control unit 100 is operably connected to the pressure sensor144 for detecting the pressure in the air circuit for rear service brakes via a link144a. The electronic control unit 100 is via the link 144a arranged to receive asignal from said means 144 representing data for pressure in the air circuit for rear service brakes.
The electronic control unit 100 is operably connected to the pressure sensor146 for detecting the pressure in the air circuit for parking brake via a link 146a.The electronic control unit 100 is via the link 146a arranged to receive a signalfrom said means 146 representing data for pressure in the air circuit for theparking brake.
The electronic control unit 100 is operably connected to the pressure sensor148 for detecting the pressure in the air circuit for the powertrain via a link148a. The electronic control unit 100 is via the link 148a arranged to receive asignal from said means 148 representing data for pressure in the air circuit for the powertrain. 19 The electronic control unit 100 is operably connected to the means 150 forcomparing the thus determined pressures detected by the respective sensorfor diagnosing the functionality of said pressure sensors via a link 150a. Theelectronic control unit 100 is via the link 150a arranged to send a signal to saidmeans 150 representing data for pressure determined by the respective DFGSSUFG SGHSOF.
The electronic control unit 100 is operably connected to the means 150 forcomparing the thus determined pressures detected by the respective sensorfor diagnosing the functionality of said pressure sensors via a link 150b. Theelectronic control unit 100 is via the link 150b arranged to receive a signal fromsaid means 150 representing data for comparison of determined pressures detected by the respective sensor.
The electronic control unit 100 is operably connected to the means 152 fordetermining a malfunction of a pressure sensor if the determined pressuredetected by that pressure sensor differs to a certain degree compared to theother pressure sensors via a link 152a. The electronic control unit 100 is viathe link 152a arranged to receive a signal from said means 152 representingdata for malfunction of a pressure sensor.
Fig. 5 schematically illustrates a block diagram of a method for diagnosingfunctionality of pressure sensors for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle comprising brakesystems of the vehicle. The distribution of pressurized air to said air circuits iscontrolled by means of an air processing system such that below a certainlower pressure level said air circuits are separated from each other, and withina pressure range above said certain lower pressure level said air circuits are in fluid connection with each other.
According to the embodiment the method for diagnosing functionality ofpressure sensors for detecting pressure level in air circuits for supplying compressed air for certain systems of a vehicle comprises a step S1. ln this step the pressure is controlled to a pressure within said pressure range.
According to the embodiment the method for diagnosing functionality ofpressure sensors for detecting pressure level in air circuits for supplyingcompressed air for certain systems of a vehicle comprises a step S2. ln this step the pressure detected by the respective pressure sensor is determined.
According to the embodiment the method for diagnosing functionality ofpressure sensors for detecting pressure level in air circuits for supplyingcompressed air for certain systems of a vehicle comprises a step S3. ln thisstep the thus determined pressures detected by the respective sensor are compared for diagnosing the functionality of said pressure sensors.
By thus comparing the determined pressure of the pressure sensors within thepressure range in which the air circuits are in fluid communication with eachother an easy and reliable way of diagnosing the pressure sensors is obtainedin that the pressure of the different pressure sensors should be the same withinthat pressure range and if not, malfunction of the differing pressure sensor canbe determined.
The air processing system comprises a multi circuit protection valve fordistribution to air systems of the vehicle for controlling the air circuits such thatthey are in fluid connection with each other within said certain pressure range above the lower pressure level.
According to an embodiment the method comprises the step of determining amalfunction of a pressure sensor if the determined pressure detected by thatpressure sensor differs to a certain degree compared to the other pressuresensors. Hereby a possible malfunction of a pressure sensor may be easilyand reliably determined.
According to an embodiment the method comprises the step of during or acertain time period changing pressure to another pressure within said pressure 21 range. Changing the pressure to another pressure within said pressure rangemay comprise Iowering the pressure which may be performed by means of avalve such as a purge valve. Changing the pressure to another pressure withinsaid pressure range may comprise increasing the pressure which may beperformed by means of a drive member, e.g. the internal combustion engineof the vehicle, for driving the compressor of the air processing system. Herebyan even more accurate diagnose is obtained in that the pressure sensors are diagnosed at another pressure level.
According to an embodiment of the method the step of during a certain timeperiod changing pressure to another pressure within said pressure rangecomprises Iowering the pressure by means of exhausting air from said air circuits. Hereby an efficient way of the changing the pressure is obtained.
According to an embodiment the method comprises the step of determiningthe amount of air exhausted from said circuits during said time period forIowering the pressure so as to determine an expected pressure difference. Bythus determining the amount of air exhausted from said circuits when Ioweringthe pressure to another pressure within the pressure range where the circuitsare in fluid communication the expected pressure decrease may bedetermined based upon the amount of exhausted air during that time periodsuch that an even more accurate diagnosing of the pressure sensors is obtained.
The method and the method steps described above with reference to fig. 5 are according to an embodiment performed with the system l according to fig. 4.
With reference to figure 6, a diagram of an apparatus 500 is shown. The controlunit 100 described with reference to fig. 4 may according to an embodimentcomprise apparatus 500. Apparatus 500 comprises a non-volatile memory520, a data processing device 510 and a read/write memory 550. Non-volatilememory 520 has a first memory portion 530 wherein a computer program, suchas an operating system, is stored for controlling the function of apparatus 500. 22 Further, apparatus 500 comprises a bus controller, a serial communicationport, I/O-means, an A/D-converter, a time date entry and transmission unit, anevent counter and an interrupt controller (not shown). Non-volatile memory 520 also has a second memory portion 540.
A computer program P is provided comprising routines for diagnosingfunctionality of pressure sensors for detecting pressure level in air circuits forsupplying compressed air for certain systems of a vehicle comprising brakesystems of the vehicle. The distribution of pressurized air to said air circuits iscontrolled by means of an air processing system such that below a certainlower pressure level said air circuits are separated from each other, and withina pressure range above said certain lower pressure level said air circuits arein fluid connection with each other. The program P comprises routines forcontrolling the pressure to a pressure within said pressure range. The programP comprises routines for determining the pressure detected by the respectivepressure sensor. The program P comprises routines for comparing the thusdetermined pressures detected by the respective sensor for diagnosing thefunctionality of said pressure sensors. The program P comprises routines fordetermining a malfunction of a pressure sensor if the determined pressuredetected by that pressure sensor differs to a certain degree compared to theother pressure sensors. The program P comprises routines for during or acertain time period changing pressure to another pressure within said pressurerange. The program routines for during a certain time period changingpressure to another pressure within said pressure range comprises routinesfor lowering the pressure by means of exhausting air from said air circuits. Theprogram P comprises routines for determining the amount of air exhaustedfrom said circuits during said time period for lowering the pressure so as todetermine an expected pressure difference. The computer program P may bestored in an executable manner or in a compressed condition in a separate memory 560 and/or in read/write memory 550. 23 When it is stated that data processing device 510 performs a certain functionit should be understood that data processing device 510 performs a certainpart of the program which is stored in separate memory 560, or a certain partof the program which is stored in read/write memory 550.
Data processing device 510 may communicate with a data communicationsport 599 by means of a data bus 515. Non-volatile memory 520 is adapted forcommunication with data processing device 510 via a data bus 512. Separatememory 560 is adapted for communication with data processing device 510via a data bus 511. Read/write memory 550 is adapted for communication withdata processing device 510 via a data bus 514. To the data communications port 599 e.g. the links connected to the control unit 100 may be connected.
When data is received on data port 599 it is temporarily stored in secondmemory portion 540. When the received input data has been temporarilystored, data processing device 510 is set up to perform execution of code in amanner described above. The signals received on data port 599 can be usedby apparatus 500 for controlling the pressure to a pressure within said pressurerange. The signals received on data port 599 can be used by apparatus 500for determining the pressure detected by the respective pressure sensor. Thesignals received on data port 599 can be used by apparatus 500 for comparingthe thus determined pressures detected by the respective sensor fordiagnosing the functionality of said pressure sensors. The signals received ondata port 599 can be used by apparatus 500 for determining a malfunction ofa pressure sensor if the determined pressure detected by that pressure sensordiffers to a certain degree compared to the other pressure sensors. The signalsreceived on data port 599 can be used by apparatus 500 for of during or acertain time period changing pressure to another pressure within said pressurerange. The signals used for during a certain time period changing pressure toanother pressure within said pressure range are used for lowering the pressureby means of exhausting air from said air circuits. The signals received on dataport 599 can be used by apparatus 500 for determining the amount of air 24 exhausted from said circuits during said time period for Iowering the pressure so as to determine an expected pressure difference.
Parts of the methods described herein can be performed by apparatus 500 bymeans of data processing device 510 running the program stored in separatememory 560 or read/write memory 550. When apparatus 500 runs the program, parts of the methods described herein are executed.
The foregoing description of the preferred embodiments of the presentinvention has been provided for the purposes of illustration and description. ltis not intended to be exhaustive or to limit the invention to the precise formsdisclosed. Obviously, many modifications and variations will be apparent topractitioners ski||ed in the art. The embodiments were chosen and describedin order to best explain the principles of the invention and its practicalapplications, thereby enabling others ski||ed in the art to understand theinvention for various embodiments and with the various modifications as are suited to the particular use contemplated.

Claims (13)

CLAIIVIS
1. A method for diagnosing functionality of at least two pressure sensors (72,74, 76, 78; 142, 144, 146, 148) used for detecting pressure level in at least twoair circuits (G1, G2, G3, G4, G5, G6) supplying compressed air to systems of avehicle, said systems comprising brake systems of the vehicle, whereindistribution of pressurized air (A1) to said air circuits (G1, G2, G3, G4, G5, G6)is controlled by means of an air processing system (l), wherein the airprocessing system (l) is adapted to separate said air circuits from each otherso that they are fluidly disconnected when the air pressure is below a firstpressure level (L3), and wherein the air processing system (l) is adapted toconnect said air circuits to each other so that they are in fluid connection witheach other when the air pressure is within a pressure range (L3-L2) above saidfirst pressure level (L3), characterized by the steps of: - controlling (S1) the pressure to a pressure (P2) within said pressure range(L3-L2); - determining (S2) the pressure detected by each pressure sensor (72, 74,76, 78; 142, 144,146,148); - comparing (S3) the thus determined pressures detected by each pressuresensor (72, 74, 76, 78; 142, 144, 146, 148); and - based on the comparison of the determined sensor pressures performing a diagnosing of the functionality of said pressure sensors.
2. A method according to claim 1, comprising the step of determining amalfunction of a pressure sensor if the determined pressure detected by thatpressure sensor differs more than a pre-determined pressure value compared to the other pressure sensors.
3. A method according to claim 1 or 2, comprising the step of during a pre-determined time period (T1) changing pressure to another pressure (P3) within said pressure range (L3-L2). 26
4. A method according to claim 3, wherein the step of during a pre-determinedtime period (T1) changing pressure to another pressure within said pressurerange (L3-L2) comprises Iowering the pressure by means of exhausting airfrom said air circuits (G1, G2, G3, G4, G5, G6).
5. A method according to claim 4, comprising the step of determining theamount of air exhausted from said circuits (G1, G2, G3, G4, G5, G6) duringsaid time period for Iowering the pressure; - determining an expected pressure reduction resulting from the exhaustionof air; - comparing the expected pressure reduction with the pressure reductiondetected by the respective pressure sensors (72, 74, 76, 78; 142, 144, 146,148); and - performing a diagnosing of the functionality of said pressure sensors alsobased on the comparison between the expected pressure reduction and thedetected pressure reduction.
6. A system (ll) for diagnosing functionality of at least two pressure sensors(72, 74, 76, 78; 142, 144, 146, 148) used for detecting pressure level in at leasttwo air circuits (G1, G2, G3, G4, G5, G6) supplying compressed air to systemsof a vehicle, said systems comprising brake systems of the vehicle, whereindistribution of pressurized air to said air circuits is controlled by means of anair processing system (I), wherein the air processing system (I) is adapted toseparate said air circuits from each other so that they are fluidly disconnectedwhen the air pressure is below a first pressure level (L3), and wherein the airprocessing system (I) is adapted to connect said air circuits to each other sothat they are in fluid connection with each other when the air pressure is withina pressure range (L3-L2) above said first pressure level (L3), characterizedby means (120) for controlling the pressure to a pressure (P2) within saidpressure range (L3-L2); means (140) for determining the pressure detected byeach pressure sensor (72, 74, 76, 78; 142, 144, 146, 148); means (150) for comparing the thus determined pressures detected by each pressure sensor; 27 and means for performing a diagnosing of the functionality of said pressure sensors based on the comparison of the determined sensor pressures.
7. A system according to claim 6, comprising means (152) for determining amalfunction of a pressure sensor if the determined pressure detected by thatpressure sensor differs more than a pre-determined pressure value compared to the other pressure sensors.
8. A system according to claim 6 or 7, comprising means (122, 124) for duringa pre-determined time period (T1) changing pressure to another pressure (P3)within said pressure range (L3-L2).
9. A system according to claim 8, wherein the means (122, 124) for during apre-determined time period changing pressure to another pressure within saidpressure range (L3-L2) comprises means (122) for Iowering the pressure by means of exhausting air from said air circuits.
10. A system according to claim 9, comprising means (130) for determining theamount of air exhausted from said circuits during said time period for Ioweringthe pressure; means for determining an expected pressure reduction resultingfrom the exhaustion of air; means for comparing the expected pressurereduction with the pressure reduction detected by the respective pressuresensors (72, 74, 76, 78; 142, 144, 146, 148); and means for performing adiagnosing of the functionality of said pressure sensors also based on thecomparison between the expected pressure reduction and the detectedpressure reduction.
11. A vehicle (1) comprising a system (l) according to any of claims 6-10.
12. A computer program (P) for diagnosing functionality of pressure sensorsfor detecting pressure level in air circuits for supplying compressed air forcertain systems of a vehicle, said computer program (P) comprising program code which, when run on an electronic control unit (100) or another computer 28 (500) connected to the electronic control unit (100), causes the electronic control unit to perform the steps according to claim 1-5.
13. A computer program product comprising a digital storage medium storing the computer program according to claim 12.
SE1650747A 2016-05-30 2016-05-30 Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle SE539928C2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
SE1650747A SE539928C2 (en) 2016-05-30 2016-05-30 Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle
DE102017004896.7A DE102017004896B4 (en) 2016-05-30 2017-05-22 Method and system for diagnosing the function of pressure sensors

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE1650747A SE539928C2 (en) 2016-05-30 2016-05-30 Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle

Publications (2)

Publication Number Publication Date
SE1650747A1 SE1650747A1 (en) 2017-12-01
SE539928C2 true SE539928C2 (en) 2018-01-16

Family

ID=60268745

Family Applications (1)

Application Number Title Priority Date Filing Date
SE1650747A SE539928C2 (en) 2016-05-30 2016-05-30 Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle

Country Status (2)

Country Link
DE (1) DE102017004896B4 (en)
SE (1) SE539928C2 (en)

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19903265A1 (en) 1999-01-28 2000-08-03 Bosch Gmbh Robert Monitoring method for motor vehicle controller, e.g. brake system, involves defining reference parameter for measured signal during test phase, detecting error if signal value varies in opposition to it
FR2945321A3 (en) 2009-05-07 2010-11-12 Renault Sas Diagnosis device operating method for diagnosing state of pressure sensor in supercharged spark ignition engine of vehicle, involves comparing pressure values provided by three pressure sensors when engine is stopped

Also Published As

Publication number Publication date
DE102017004896A1 (en) 2017-11-30
SE1650747A1 (en) 2017-12-01
DE102017004896B4 (en) 2023-06-29

Similar Documents

Publication Publication Date Title
US7413266B2 (en) Method for controlling the brake system of a vehicle train
KR102096452B1 (en) Method for detecting leaks in a brake pressure line, under braking pressure, of a rail vehicle
CN104010896B (en) For the method and apparatus carrying out the distribution of electronics regulating brake force according to differential skidding
RU2487807C2 (en) Method and device for testing braking of vehicle with trailer and/or semi-trailer
US8897957B2 (en) Control and monitoring device of a vehicle having a tire-monitoring control unit and a brake control unit integrated in a subassembly
CN101801747B (en) Electropneumatic parking brake modulator for a trailer in a vehicle/trailer combination
US8560162B2 (en) Monitoring device for monitoring systems of a vehicle
KR101248715B1 (en) Control unit for a rail vehicle
US5986544A (en) Method and apparatus for detecting a trailer towing mode for a motor vehicle
US8543305B2 (en) Method and device for assessing the compatability of braking systems of a vehicle combination
CA2725205C (en) Single channel roll stability system
CN102666228B (en) There is the vehicle operation brake equipment of valve trail run
CN104870274B (en) The braking energy adjusting method of vehicle combination, EBS control devices and vehicle combination
RU2671803C2 (en) Vehicle brake management device
US8392052B2 (en) Vehicle inspection apparatus
US20150102921A1 (en) Micro leakage detecting device of suspension device and method for detecting micro leakage
US20070138865A1 (en) Single channel roll stability system
US20230089211A1 (en) Method for testing a select-high valve
JPH08244594A (en) Method and equipment for testing function of electronic type control brake device
US20060232127A1 (en) Method for monitoring a braking torque modification of a retarder
SE539928C2 (en) Method and system for diagnosing functionality of pressure sensors in air circuits of a vehicle
CN108602505A (en) Method for detecting and compensating the leakage in brake apparatus
CN108025712A (en) For running the method for the braking control system for the rail vehicle with braking system, braking control system, braking system and rail vehicle
KR20190015179A (en) Open loop control unit, axle modulator and braking system
CN111328312A (en) System and method for performing diagnostics on a vehicle hydraulic system in a stopped state