CN113460021A

CN113460021A - Signal diagnosis method based on brake sensor, brake sensor system and automobile

Info

Publication number: CN113460021A
Application number: CN202110797955.4A
Authority: CN
Inventors: 秦志强; 杨日钊; 陈富强; 黄真; 吴颂; 周晓刚; 何洋霄; 王斯怡; 杨家厂
Original assignee: Dongfeng Liuzhou Motor Co Ltd
Current assignee: Dongfeng Liuzhou Motor Co Ltd
Priority date: 2021-07-14
Filing date: 2021-07-14
Publication date: 2021-10-01
Anticipated expiration: 2041-07-14
Also published as: CN113460021B

Abstract

The invention belongs to the technical field of brake control, and discloses a signal diagnosis method based on a brake sensor, a brake sensor system and an automobile, wherein the signal diagnosis method based on the brake sensor comprises the following steps: acquiring a running state and a brake lamp signal and a brake switch signal acquired by a brake sensor; determining a fault condition according to the brake lamp signal, the brake switch signal and the driving state; when the fault condition is met, counting a fault count value through a fault counter; determining a fault threshold value according to the fault condition; and when the fault count value exceeds a fault threshold value, determining a diagnosis result of the brake synchronism fault. The invention diagnoses and records the synchronism fault by distinguishing the fault triggering conditions under different working conditions, ensures the adaptability and rationality of working condition diagnosis and can effectively detect the synchronism abnormity of two paths of signals of the sensor in a multi-path way.

Description

Signal diagnosis method based on brake sensor, brake sensor system and automobile

Technical Field

The invention relates to the field of brake control, in particular to a signal diagnosis method based on a brake sensor, a brake sensor system and an automobile.

Background

In the existing passenger vehicle manufacturing system, a brake switch/sensor is a brake pedal state monitoring device which is necessary for a vehicle, and in order to realize a brake priority function and simultaneously realize two functions of lighting a brake lamp at the moment of stepping on a brake pedal through the sensing device, the brake switch/sensor is generally designed into a two-way output signal device with opposite states, wherein a normally closed loop is called a brake switch signal, called BRS for short, and is used for inputting the brake state into an engine ECU; the normally open circuit is called a brake light signal, called BLS for short, and is used for representing the lighting state of the brake light.

The trigger structure of the brake sensor is a telescopic probe compressed by a spring, the BRS is normally closed and the BLS is normally open through assembly with a brake pedal, and when the brake pedal is stepped on, the BRS is disconnected and the BLS is closed. In order to ensure the safety of braking, the mutual reversal and synchronism of two paths of signals are the most important indexes. The diagnosis of the brake sensor signal is divided into two types, namely, circuit driving level diagnosis and synchronization (rationality) diagnosis. Due to the physical and electrical characteristics of the brake sensor, two paths of signals are not synchronous inevitably due to the hysteresis of physical action/electrical signals, and meanwhile, the two paths of signals are not synchronous due to the fact that the sensor probe is located at a critical point easily triggered by assembly errors, and synchronous faults caused by the reasons are not continuous real faults, but can cause fault reporting to further influence vehicle control.

The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.

Disclosure of Invention

The invention mainly aims to provide a signal diagnosis method based on a brake sensor, and aims to solve the technical problem that a synchronization fault is easy to misreport due to the fact that two paths of signals are asynchronous in the prior art.

In order to achieve the above object, the present invention provides a brake sensor-based signal diagnosis method, including the steps of:

acquiring a running state and a brake lamp signal and a brake switch signal acquired by a brake sensor;

determining a fault condition according to the brake lamp signal, the brake switch signal and the driving state;

when the fault condition is met, counting a fault count value through a fault counter;

determining a fault threshold value according to the fault condition;

and when the fault count value exceeds a fault threshold value, determining a diagnosis result of the brake synchronism fault.

Optionally, after acquiring the driving state and the brake light signal and the brake switch signal collected by the brake sensor, the method further includes:

when the brake lamp signal and the brake switch signal meet the reset condition, resetting the fault count value in the corresponding fault counter;

when the fault condition is met, counting fault count values through a fault counter, wherein the counting comprises the following steps:

and when the fault condition is met, counting the fault count value through the fault counter after zero clearing.

Optionally, the step of determining a fault condition according to the stop lamp signal, the brake switch signal and the driving state includes:

when the running state is a braking state, determining that a fault condition is a first fault condition;

when the brake lamp signal and the brake switch signal are not synchronous and the running state is a non-braking state, determining that the fault condition is a second fault condition;

and when the stop lamp signal is synchronous with the brake switch signal and the running state is a non-braking state, determining that the fault condition is a third fault condition.

Optionally, the fault counters include a first fault counter corresponding to the first fault condition, a second fault counter corresponding to the second fault condition, and a third fault counter corresponding to the third fault condition;

when the fault condition is met, the step of counting the fault count value through the fault counter comprises the following steps:

when the first fault condition is met, counting fault count values through the first fault counter;

when the second fault condition is met, counting fault count values through the second fault counter;

and when the third fault condition is met, counting the fault count value through the third fault counter.

Optionally, the step of determining a fault threshold according to the fault condition includes:

when the fault condition is a first fault condition, determining that the fault threshold is a first fault threshold;

when the fault condition is a second fault condition, determining that the fault threshold is a second fault threshold;

and when the fault condition is a third fault condition, determining that the fault threshold is a third fault threshold.

Optionally, after the step of determining a diagnosis result of the brake synchronicity fault when the fault count value exceeds a fault threshold value, the method further includes:

and recording a fault code when a synchronism fault is detected in n continuous driving cycles, wherein n is greater than or equal to 2.

Optionally, after the step of recording a fault code when a synchronism fault is detected in n consecutive driving cycles, the method further comprises:

clearing the fault code when no synchronicity fault is detected in N consecutive driving cycles, wherein N is larger than or equal to N.

In addition, to achieve the above object, the present invention also proposes a brake sensor system that can perform the brake sensor-based signal diagnosis method as described above; the brake sensor system comprises a first power supply, a second power supply and a brake; the brake comprises a pedal and first to fourth contacts, the first contact is connected with the first power supply, the second contact is connected with an engine management system, the third contact is connected with the second power supply, and the fourth contact is connected with the engine management system.

Optionally, the pedal is used for switching the brake switch circuit and the brake lamp circuit to be on and off;

when the pedal does not act, the first contact is connected with the second point through the pedal, and a brake switch loop is conducted;

when the pedal acts, the third contact and the fourth contact are connected through the pedal, and a stop lamp loop is conducted.

In addition, to achieve the above object, the present invention further provides a vehicle including the brake sensor system as described above.

The invention obtains the running state and the brake lamp signal and the brake switch signal collected by the brake sensor; determining a fault condition according to the brake lamp signal, the brake switch signal and the driving state; when the fault condition is met, counting a fault count value through a fault counter; determining a fault threshold value according to the fault condition; and when the fault count value exceeds a fault threshold value, determining a diagnosis result of the brake synchronism fault. The synchronous fault is diagnosed and recorded by distinguishing the fault triggering conditions under different working conditions, so that the adaptability and rationality of working condition diagnosis are ensured, and the synchronization abnormity of two paths of signals of the sensor can be effectively detected in a multi-path manner.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic diagram of a brake sensor system in a hardware operating environment according to an embodiment of the present invention;

FIG. 2 is a schematic flow chart of a first embodiment of a brake sensor based signal diagnostic method of the present invention;

FIG. 3 is a schematic flow chart of a second embodiment of a brake sensor based signal diagnostic method of the present invention;

FIG. 4 is a schematic flow chart of a third embodiment of a brake sensor based signal diagnostic method of the present invention;

fig. 5 is a schematic flow chart of a fourth embodiment of the brake sensor-based signal diagnosis method according to the present invention.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				V1	A first power supply	01～04	First to fourth contacts
V2	Second power supply	10	Engine management system
				00	Brake	BRS	Brake switch circuit
001	Pedal	BLS	Brake lamp loop

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should be considered to be absent and not within the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a brake sensor system in a hardware operating environment according to an embodiment of the present invention.

As shown in fig. 1, the brake sensor system includes a first power source V1, a first power source V2, and a brake 00; the brake 00 comprises a pedal 001 and first to fourth contacts 01-04, wherein the first contact 01 is connected with the first power source V1, the second contact 02 is connected with the engine management system 10, the third contact 03 is connected with the first power source V2, and the fourth contact 04 is connected with the engine management system 10. The first contact 01 and the second contact 02 are normally closed, and the third contact 03 and the fourth contact 04 are normally open.

Further, the pedal 001 is configured to switch the brake switch circuit BRS and the brake lamp circuit BLS on and off.

When the pedal 001 is not operated, the first contact 01 and the second contact are connected through the pedal 001, and a brake switch circuit BRS is turned on. In this embodiment, when the pedal 001 is not operated, the running state is determined to be the unbraked state, and at this time, the brake switch signal is to be invalidated, the stop lamp signal is also invalidated, BRS is 0, and BLS is 0.

When the pedal 001 operates, the third contact 03 and the fourth contact 04 are connected to each other through the pedal 001, and the stop lamp circuit BLS is turned on. In this embodiment, when the pedal 001 is actuated, the driving state is determined to be a braking state, and at this time, the brake switch signal should be active, the brake light signal should also be active, BRS is 1, and BLS is 1.

Those skilled in the art will appreciate that the configuration of the apparatus shown in FIG. 1 does not constitute a limitation of a brake sensor system and may include more or fewer components than shown, or some components in combination, or a different arrangement of components.

Further, referring to fig. 2, fig. 2 is a schematic flow chart of a first embodiment of the brake sensor-based signal diagnosis method according to the present invention;

the signal diagnosis method based on the brake sensor comprises the following steps:

step S100: and acquiring a running state and a brake lamp signal and a brake switch signal acquired by a brake sensor.

In this embodiment, the executing entity may be an engine management system, and may also be other devices that can achieve the same or similar functions, which is not limited by this embodiment.

Step S200: and determining a fault condition according to the brake lamp signal, the brake switch signal and the running state.

It should be noted that the fault condition may be one-to-one corresponding to the vehicle operating condition, that is, a corresponding fault condition is set in any one operating condition that can be represented by the combination of the three factors, that is, the stop lamp signal, the brake switch signal, and the driving state, and the fault condition is a determination standard for determining the start count, and may be set manually after the test and the related data analysis of the vehicle brake sensor system are performed in the specific implementation, and stored in the engine management system in a programming manner. In a specific implementation, the fault condition may be defined according to an actual situation, and the embodiment does not limit this.

Step S300: and when the fault condition is met, counting a fault count value through a fault counter.

It should be noted that, because synchronous faults are different in expression form according to different working conditions, in order to avoid false alarm and differentiation, the number of fault counters corresponds to the fault conditions one by one, that is, there are many fault conditions, there are many fault counters, and when a fault condition is satisfied, it is only necessary to add 1 to the fault count value in the corresponding fault counter, thereby completing the statistics of the fault count value once.

Step S400: and determining a fault threshold according to the fault condition.

It can be understood that the fault threshold is a specific value, the standard for judging the synchronous fault is different in the frequency of the fault under different working conditions, and therefore the standard for judging the brake synchronous fault is different under each fault condition. After the test and the related data analysis of the automobile brake sensor system are carried out, the fault threshold value is set artificially and stored in an engine management system in a programming mode. In a specific implementation, the fault condition may be defined according to an actual situation, and the embodiment does not limit this.

Step S500: and when the fault count value exceeds a fault threshold value, determining a diagnosis result of the brake synchronism fault.

It can be understood that when the fault count value in any fault counter exceeds the corresponding fault threshold value, the diagnosis result of the brake synchronism fault can be determined.

According to the method, a fault condition is determined according to a running state, a brake lamp signal and a brake switch signal which are acquired by a brake sensor and the brake lamp signal, the brake switch signal and the running state; and when the fault condition is met, counting a fault count value through a fault counter, determining a fault threshold value according to the fault condition, and when the fault count value exceeds the fault threshold value, determining a diagnosis result of the brake synchronization fault. The synchronous fault is diagnosed and recorded by distinguishing the fault triggering conditions under different working conditions, so that the adaptability and rationality of working condition diagnosis are ensured, and the synchronization abnormity of two paths of signals of the sensor can be effectively detected in a multi-path manner.

A second embodiment of the brake sensor-based signal diagnosis method according to the present invention is proposed based on the first embodiment, and referring to fig. 3, fig. 3 is a schematic flow chart of the second embodiment of the brake sensor-based signal diagnosis method according to the present invention;

in this embodiment, after step S100, the method further includes:

step S110: and when the brake lamp signal and the brake switch signal meet the reset condition, resetting the fault count value in the corresponding fault counter.

It can be noted that the reset condition is that a normal jump is detected in the process of increasing the fault count value under a corresponding working condition, the normal jump is in one-to-one correspondence with the fault condition, and a technician can define the reset condition and store the reset condition in a program.

The step S300 includes:

step S300': and when the fault condition is met, counting the fault count value through the fault counter after zero clearing.

It is understood that after the fault count value in the fault counter is cleared, the fault counter can start counting from 0 again when the corresponding fault condition is met next time, and each time the fault count value is counted, the fault count value is also increased by 1.

In the embodiment, the two paths of signals are set in the strategy to be reset after the signals are recovered to be normal, the counting of the fault counter is decreased after the two paths of signals which are widely adopted in the market and are different from the two paths of signals which are widely adopted in the market are recovered to be normal, the synchronous fault false alarm of the brake sensor caused by large assembly deviation can be effectively avoided, and meanwhile, the detection sensitivity of real sensor faults can not be reduced.

A third embodiment of the brake sensor-based signal diagnosis method according to the present invention is proposed based on the second embodiment, and referring to fig. 4, fig. 4 is a schematic flow chart of the brake sensor-based signal diagnosis method according to the third embodiment of the present invention;

in this embodiment, the step S200 includes:

step S210: and when the running state is a braking state, determining that the fault condition is a first fault condition.

It is understood that in the braking state, the normal two signals are the brake light signal and the brake switch signal, i.e. the engine management system input state is BRS ═ 1 and BLS ═ 1.

In this embodiment, the first fault condition is that the two signals are not synchronized (i.e., BRS is 0, BLS is 1, BRS is 1, and BLS is 0) for more than 2 s. In a specific implementation, the time value in the first fault condition may be adjusted and reset according to actual conditions and needs, and this embodiment does not limit this.

The reset condition corresponding to the first failure condition is that BRS and BLS are simultaneously enabled after BRS and BLS are simultaneously disabled.

Step S220: and when the stop lamp signal and the brake switch signal are not synchronous and the running state is the non-braking state, determining that the fault condition is a second fault condition.

It is understood that in the non-braking state, the normal two signals should be the brake light signal is invalid and the brake switch signal is invalid, i.e. the engine management system input state is BRS ═ 0 and BLS ═ 0.

In the present exemplary embodiment, the first fault condition is that the two signals are not simultaneously active (i.e., BRS is 0, BLS is 1, BRS is 1, BLS is 0), but the vehicle deceleration is > 5m/s²Over 1 s. In a specific implementation, the acceleration value and the time value in the second fault condition may be adjusted and reset according to actual conditions and needs, and this embodiment does not limit this.

The reset condition corresponding to the second failure condition is that BRS and BLS are simultaneously enabled after BRS and BLS are simultaneously disabled.

Step S230: and when the stop lamp signal is synchronous with the brake switch signal and the running state is a non-braking state, determining that the fault condition is a third fault condition.

In this embodiment, the first fault condition is that both signals are active at the same time (i.e., BRS 1 and BLS 1), but the vehicle is moving at a forward acceleration in the range of 20km/h to 90km/h per hour. In a specific implementation, the speed value in the third fault condition may be adjusted and reset according to actual conditions and needs, and this embodiment does not limit this.

After the reset conditions BRS and BLS corresponding to the second failure condition are simultaneously invalidated, the BRS and BLS are simultaneously validated but the failure counter is not started.

Further, the fault counters include a first fault counter corresponding to the first fault condition, a second fault counter corresponding to the second fault condition, and a third fault counter corresponding to the third fault condition;

the step S300 includes:

and when the first fault condition is met, counting fault count values through the first fault counter.

It can be understood that the first failure counter is a functional module with a counting function divided in the engine management system, the first failure counter is only used for recording the number of times that the first failure condition is met, each time the first failure condition is met, the failure count value in the first failure counter is only added by 1, and when the BRS and the BLS are restored to the simultaneously invalid state, the first failure counter completes counting for 1 time.

And when the second fault condition is met, counting the fault count value through the second fault counter.

It can be understood that the second failure counter is a functional module with a counting function divided in the engine management system, the second failure counter is only used for recording the number of times that the second failure condition is met, each time the second failure condition is met, the failure count value in the second failure counter is only increased by 1, and when the BRS and the BLS are restored to the simultaneously invalid state, the second failure counter completes counting for 1 time.

It can be understood that the third failure counter is a functional module with a counting function divided in the engine management system, the third failure counter is only used for recording the number of times that the third failure condition is met, each time the third failure condition is met, the failure count value in the third failure counter is only increased by 1, and when the BRS and the BLS are restored to the simultaneously invalid state, the third failure counter completes counting for 1 time.

Further, the step S400 includes:

when the fault condition is a first fault condition, determining that the fault threshold is a first fault threshold.

It will be appreciated that the first fault threshold is a specific value that serves as a criterion for diagnosing a synchronous fault under first fault conditions, and in this embodiment is 20. After the test and the related data analysis of the automobile brake sensor system are carried out, the fault threshold value is set artificially and stored in an engine management system in a programming mode. In a specific implementation, the fault condition may be defined according to an actual situation, and the embodiment does not limit this.

And when the fault condition is a second fault condition, determining that the fault threshold is a second fault threshold.

It will be appreciated that the second fault threshold is a specific value used as a criterion for diagnosing a synchronous fault under the second fault condition, and in this embodiment, the second fault threshold is 10. After the test and the related data analysis of the automobile brake sensor system are carried out, the fault threshold value is set artificially and stored in an engine management system in a programming mode. In a specific implementation, the fault condition may be defined according to an actual situation, and the embodiment does not limit this.

It will be appreciated that the third fault threshold is a specific value used as a criterion for diagnosing a synchronous fault under a third fault condition, and in this embodiment, the third fault threshold is 5. After the test and the related data analysis of the automobile brake sensor system are carried out, the fault threshold value is set artificially and stored in an engine management system in a programming mode. In a specific implementation, the fault condition may be defined according to an actual situation, and the embodiment does not limit this.

According to the embodiment, three fault counters are set to cover two-path signal synchronization abnormity high-occurrence working conditions, and the fault counter trigger fault threshold values are set according to different probabilities of three situations, so that the adaptability and the rationality of working condition diagnosis are ensured, and the two-path signal synchronization abnormity of the sensor can be effectively detected in a multi-path mode.

A fourth embodiment of the brake sensor-based signal diagnosis method according to the present invention is proposed based on the third embodiment, and referring to fig. 5, fig. 5 is a schematic flow chart of the brake sensor-based signal diagnosis method according to the fourth embodiment of the present invention;

in this embodiment, after the step S500, the method further includes:

step S600: and recording a fault code when a synchronism fault is detected in n continuous driving cycles, wherein n is greater than or equal to 2.

It should be noted that the driving cycle refers to one ignition and flameout of the engine, and the fault code is uploaded to the driving computer by the engine management system after being recorded, and at this time, the cruise cannot be performed, and the ECU safety monitoring cannot be performed.

In the present embodiment, n is 2. In a specific implementation, n may be set according to different automobile models and other hardware conditions, and the embodiment does not limit this.

Further, after the step S600, the method further includes:

In the present embodiment, N is 40. In a specific implementation, N may be set according to different automobile models and other hardware conditions, and this embodiment does not limit this.

According to the embodiment, the vehicle is prohibited from cruising after the synchronous fault is reported by a strategy of appointing the synchronous fault code report, so that the driving safety of the vehicle is ensured.

In addition, the embodiment of the invention also provides an automobile, and the automobile comprises the brake sensor system.

Since the automobile adopts all the technical solutions of all the embodiments, at least all the beneficial effects brought by the technical solutions of the embodiments are achieved, and no further description is given here.

It should be understood that the above is only an example, and the technical solution of the present invention is not limited in any way, and in a specific application, a person skilled in the art may set the technical solution as needed, and the present invention is not limited thereto.

It should be noted that the above-described work flows are only exemplary, and do not limit the scope of the present invention, and in practical applications, a person skilled in the art may select some or all of them to achieve the purpose of the solution of the embodiment according to actual needs, and the present invention is not limited herein.

In addition, the technical details that are not elaborated in this embodiment may be referred to a signal diagnosis method based on a brake sensor provided in any embodiment of the present invention, and are not described herein again.

Further, it is to be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solution of the present invention or portions thereof that contribute to the prior art may be embodied in the form of a software product, where the computer software product is stored in a storage medium (e.g. Read Only Memory (ROM)/RAM, magnetic disk, optical disk), and includes several instructions for enabling a terminal device (e.g. a mobile phone, a computer, a server, or a network device) to execute the method according to the embodiments of the present invention.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A brake sensor based signal diagnostic method, characterized in that the brake sensor based signal diagnostic method comprises the steps of:

determining a fault threshold value according to the fault condition;

2. The brake sensor-based signal diagnosis method according to claim 1, wherein after acquiring the driving state and the brake light signal and the brake switch signal collected by the brake sensor, the method further comprises:

3. The brake sensor-based signal diagnosis method according to claim 1, wherein the step of determining a fault condition based on the stop lamp signal, the brake switch signal and the driving state comprises:

4. The brake sensor-based signal diagnostic method of claim 3, wherein the fault counters include a first fault counter corresponding to the first fault condition, a second fault counter corresponding to the second fault condition, and a third fault counter corresponding to the third fault condition;

5. A brake sensor based signal diagnostic method according to claim 3, wherein said step of determining a fault threshold based on said fault condition comprises:

6. The brake sensor-based signal diagnostic method of claim 1, wherein after the step of determining a diagnostic result of a brake synchronicity fault when the fault count value exceeds a fault threshold, the method further comprises:

7. The brake sensor based signal diagnostic method of claim 6, wherein after the step of recording a fault code when a synchronization fault is detected in n consecutive driving cycles, the method further comprises:

8. A brake sensor system, characterized in that it can perform a brake sensor based signal diagnosis method according to any one of claims 1 to 7; the brake sensor system comprises a first power supply, a second power supply and a brake; the brake comprises a pedal and first to fourth contacts, the first contact is connected with the first power supply, the second contact is connected with an engine management system, the third contact is connected with the second power supply, and the fourth contact is connected with the engine management system.

9. The brake sensor system according to claim 8, wherein the pedal is configured to switch the brake switch circuit and the brake lamp circuit on and off;

10. A vehicle, characterized in that it comprises a brake sensor system according to claim 8 or 9.