EP3411580B1 - Method for resetting two pressure sensors in an air-intake line of an engine with sensor fault prevention - Google Patents

Description

The present invention relates to a method of readjusting at least two pressure sensors positioned in an air intake line of an internal combustion engine with prevention of a fault in one of the sensors, the detection of a fault in one of the sensors causing the suspension of the implementation of the method.

The invention lies in the technical field of the command and control system of an internal combustion engine which is preferably with spark ignition.

Frequently, in an air intake line of an internal combustion engine, three pressure sensors are present, namely an atmospheric pressure sensor, a boost pressure sensor, this when the engine is turbocharged. , the boost pressure sensor located downstream of a compressor of a turbocharger and an intake pressure sensor positioned in the air distributor. These three sensors are used to measure the pressure existing at certain specific points on the air intake line.

The measurement of the same pressure by several sensors can give different values, due to their intrinsic and evolving precision. This occurs in particular with the engine stopped, for which the pressure measured by each sensor is atmospheric pressure, which will not necessarily be the case in engine operation.

It is therefore necessary to readjust these pressure sensors before their use, this readjustment being done when the engine stops before starting the vehicle. The adjustment of the pressure sensors consists in compensating for this offset, in order to equalize the values measured on the sensors when the pressure to be measured is the same. This operation is particularly necessary for the correct operation of the piloting of a positive-ignition engine.

Currently, a method of readjusting the pressure sensors of the air intake line is known. The steps of this registration process are as follows. When the engine stops, the three sensors measure the same pressure: atmospheric pressure. We therefore take advantage of this phase of life to achieve registration.

For this readjustment, a reference sensor is chosen by calibration. It is in relation to the measurement of this sensor that the other sensors will be readjusted. This reference sensor must be the most accurate sensor. This is frequently the case for an atmospheric pressure sensor which is most often preferred as a reference sensor.

Upon initialization of an on-board computer in the motor vehicle and carrying out the control command of the powertrain as well as of its auxiliary elements, a timer is started. This delay makes it possible, on the one hand, to ensure that the intake line is at equilibrium of atmospheric pressure, and on the other hand, to ensure that the sensors are in a state allowing them to perform a consistent measure. During this time delay, the differences in measured values between the reference sensor and each sensor to be readjusted are determined.

At the end of this time delay, these differences are then added to the values of the sensors to be readjusted to compensate for the offset. In order to ensure that the resetting is carried out in most starting cases, even rapid starts for which the engine has been left at a standstill only briefly, the time delay is calibrated very short. Its order of magnitude is 300 milliseconds.

If the actuation of the motor takes place before the end of the time delay, then the readjustment is inhibited because it is considered that the readjustment is not reliable enough, the measured values having been distorted due to the fact that one or more pressure sensors were not in their optimal working condition.

The figure 1 illustrates a chronogram as a function of time t of the process for resetting the pressure sensors according to the prior art, the resetting process having taken place correctly while the figure 2 illustrates a chronogram as a function of time t of the same process according to the state of the art, the start having been suspended by a failure of the resetting in the determined time before start.

To the Figures 1 and 2 , the atmospheric pressure, supercharging and air intake sensors are referenced respectively Capatm, Capsural and Capadmi. These sensors are shown in these two figures at the top of the figure on the left not readjusted Capnrecal then at the top of the figure on the right readjusted Caprecal. An initial Div divergence between the Capatm, Capsural and Capadmi sensors to be reset is more significant at the figure 2 that at the figure 1 .

From the establishment of an electrical contact triggering the alarm clock I of an on-board computer embedded in the motor vehicle, the chronogram of Figures 1 and 2 shows a time delay T for resetting R of the sensors then a start D of the engine.

To the figure 1 , the sensors were readjusted in time and the start could take place. To the figure 2 , it was estimated that the sensors could not be readjusted in time, which does not necessarily correspond to reality. It is then issued by a Pancap control element a failure notice which indicates a Def failure which prevents starting, non starting being referenced nD to the figure 2 which illustrates this case.

To the figure 2 , mismanagement of a sensor fault detection is illustrated, this mismanagement can lead to a situation where the engine cannot start. When the diagnosis of the air intake line sensors is carried out, there is a certain amount of time before confirmation and the recovery of a Def fault, this recovery may occur after the actual resetting of the sensors R.

Def defect can be raised by issuing a reconfiguration flag, also known by the Anglo-Saxon name of flag. The reconfiguration flag is a Boolean variable in the engine control software representing the state of a diagnosis. When a diagnosis is carried out, if a fault is detected and confirmed, then the reconfiguration flag associated with this diagnosis is worth 1. If there is no confirmed fault, then it is worth 0.

The reconfiguration flag identifies a failure of a pressure sensor and the engine control functions use this flag to activate recovery strategies in the event of a sensor failure.

The transmission time of a configuration flag can be of the order of 2 seconds and is to be compared with that of the registration delay and the need for rapid application of registration. Thus, in the event of a defect in the reference sensor, most often the Capatm atmospheric air pressure sensor, the sensor failure is not signaled until after the registration has been applied. The diagnosis is therefore not useful. But above all, the registration will be carried out from erroneous values, for example a value 0.

In addition, in the closest prior art, there is no consideration of the temperature of the pressure sensors for the calculation of the registration. This can lead to a significant deterioration in the accuracy of the sensor. The driving performance of the vehicle is then degraded and even it may be impossible to start.

A pressure sensor has a measurement accuracy which depends on its temperature. Generally, the accuracy is optimal in the temperature range 0 ° C-90 ° C. It becomes much larger when the sensor is very cold (<0 ° C) or very hot (> 90 ° C).

The figure 3 illustrates the evolution of the error ranges as a function of the temperature respectively for two specific pressure sensors, namely a Capatm atmospheric pressure sensor and a Capsural boost sensor. The temperature is indicated on the abscissa with ordinates of error multiplier values.

For each sensor, a template comprising two curves delimits the range of errors for a succession of temperatures. The two dotted curves are associated with the Capsural boost sensor while the two solid lines are associated with the Capatm atmospheric pressure sensor. The curves for each sensor are different with a higher margin of error for the values of the Capsural boost sensor than for the Capatm atmospheric pressure sensor.

For example, a Capatm atmospheric pressure sensor is accurate to +/- 15mb in the 0-85 ° C area, while a Capsural boost pressure sensor is accurate to +/- 25mb in the same area. The same applies for an air intake pressure sensor positioned in an air distributor as for a Capsural boost pressure sensor, without the size of this intake pressure sensor being shown in the figure 2 .

A maximum compensation of Crmax (T1) and Crmax (T) respectively for a temperature T1 or T can be defined between the points furthest from each other by one of the curves of the Capatm atmospheric pressure sensor with a curves of the Capsural boost sensor, between the highest curve of the Capsural boost sensor and the lowest curve of the Capatm atmospheric sensor.

For example, taking as reference sensor the atmospheric pressure sensor Capatm, when the maximum registration compensation Crmax (T1), previously taken for the temperature T1, is applied in the middle zone of Optimal accuracy of the sensors for the Capsural boost sensor, for example at temperature T, this can cause the accuracy of this Capsural boost sensor to go outside the intrinsic precision limits of its size.

The figure 3 shows that by keeping the same registration compensation for all temperatures, the accuracy of the pressure measurement is degraded by a specific sensor. This can lead to unacceptable situations, for example of non-starting or loss of performance of the internal combustion engine, for example by the false determination of a target torque of the engine.

The document US-B-7 668 687 describes a system which makes it possible to carry out corrections on pressure sensors by comparing the pressures of the sensors with one another, with the engine stopped. This corresponds to the readjustment of the sensors with respect to each other. On the other hand, this document gives no indication as to the prevention of a defect in a sensor, the detection of such a defect causing the suspension of the implementation of the registration process. The same goes for possible compensation for a recalibration of a sensor or pressure sensors taking into account the temperature variation near the sensors. Other systems which allow correction of pressure sensors using a corrective term are known from the documents EP1193385A2 , DE10261382A1 and WO2010004152A1 .

Consequently, the problem underlying the invention is to optimize a method of readjusting sensors present in an air intake line of an engine with a detection of a sensor failure which is effective while does not prevent the proper functioning of the engine and in particular its starting.

To achieve this objective, there is provided according to the invention a method of readjusting at least two pressure sensors positioned in an air intake line of an internal combustion engine, in which said at least two sensors pressure are readjusted by a compensation compensation calculated for at least a second sensor with respect to a first pressure sensor serving as a reference sensor between their respective pressure measurements at a temperature known as initial of the sensors during an engine stop, this registration compensation then being applied to said at least one second sensor for correction of its pressure measurements, characterized in that, prior to the application of registration compensation on said at least one second sensor, a step internal diagnostic based on the value of the compensation for shifting consisting in determining if the compensation for shifting exceeds a value of maximum compensation, in which case it is diagnosed that one of said at least two sensors is faulty and in that, in this case, the application of the compensation for registration is suspended.

The technical effect is to obtain a readjustment process of at least two pressure sensors which is freed from the times necessary for the development of diagnoses, this by carrying out a diagnosis directly internally faster. This eliminates completely the situations of non-start-up or loss of performance caused by a readjustment process according to the state of the art requiring a long time to develop a diagnosis.

If the internal diagnosis finds a fault, then readjustment is prohibited and is not carried out. This allows, on the one hand, not to reset the sensors to inconsistent values when the internal diagnosis indicates a failure and, on the other hand, to reset the sensors more quickly when the internal diagnosis indicates no failure.

The solution proposed by the present invention is a software solution, simple to implement, since it can immediately be integrated into an engine control. It is also very inexpensive since it does not require additional equipment. This solution is essential because the resetting of the sensors is crucial for the proper functioning of the control of the air flow in the engine which cannot function correctly without this resetting.

Advantageously, the registration is done on at least three pressure sensors with a first reference sensor among said at least three sensors and, if the compensation compensation between the first sensor and respectively the second and third sensors both exceed the value of maximum compensation, it is diagnosed that the first sensor has failed, while, if the compensation compensation of the first sensor exceeds the maximum compensation value with one of the second and third sensors then it does not exceed the maximum value with the other of the second or third sensors, it is diagnosed that the second or the third sensor associated with a compensation for adjustment which exceeds the maximum compensation value has failed.

Thus, it can easily be determined which sensor of the three sensors present is faulty, the probability that two sensors are simultaneously faulty being very low.

Advantageously, the maximum compensation value is specific to the pair or to each pair formed by said at least two sensors, the maximum compensation value being greater than 20 or 30 millibars.

Advantageously, a respective error mask as a function of the temperature of the sensor is developed for each sensor, the error mask of each sensor defining an error range for each temperature, the compensation for registration being calculated from the difference. respective pressure measurements of said at least two sensors at the initial temperature.

Advantageously, a temperature measurement step is carried out before said registration compensation at the level of said at least two sensors and, if the temperature is not within a predetermined temperature interval, registration compensation is suspended, this interval being from 0 to 85 ° C.

This avoids falling into the situation where the performance of the sensors is degraded due to a registration carried out hot or cold, that is to say below 0 ° C and above 85 ° C by setting up a readjustment inhibition system.

This makes it possible to work with sensors reset in an area of optimal sensor accuracy. Outside this precision zone, there would be a possibility of deterioration of the precision of the sensors due to too great a maximum compensation of registration. By taking into account the temperature of the sensors, the situations of non-starting or loss of performance caused by the process are completely eliminated according to the closest prior art.

Advantageously, after application of the compensation compensation on said at least one second sensor, it is expected for a predetermined time interval sufficient to carry out a verification that the state of said at least two sensors allows them to carry out a coherent pressure measurement and if it is found that a sensor is not in a condition to carry out a coherent pressure measurement, the application of the compensation for registration is canceled, this time interval being approximately two seconds. Thus, after the internal diagnosis enabling the sensor diagnostic time to be dispensed with, a system for waiting for the reading of the verification made by a diagnosis external to the sensor is set up, in order to confirm or cancel the registration. .

This verification is essentially based on an external diagnosis which can be done by control elements external to the sensor. This external diagnosis is more complete than the internal diagnosis previously carried out, but takes more time. This is why the invention first of all provides for carrying out an internal diagnosis so as not to have a problem waiting for the internal diagnosis which could lead to a non-start up, this internal diagnosis being verified by the longer external diagnosis Implementation.

It is thus planned to complete this internal diagnosis which may be false or incomplete by a more complete verification but requiring more time while still implementing the default registration process, at least temporarily.

Indeed, if this verification indicates a failure of one or more sensors, the registration process is canceled because it is considered to distort the accuracy of the sensors. The readjustment process will then have been applied only for a reduced duration which has little or no consequence on the optimal operation of the engine.

The invention relates to a powertrain comprising an internal combustion engine with an air intake line to the engine, the line comprising a first and at least a second pressure sensor, characterized in that said at least one second sensor pressure is readjusted relative to the first pressure sensor according to a readjustment method as described above.

Advantageously, the first and said at least one second pressure sensor are selected from an atmospheric pressure sensor, a boost sensor positioned downstream of a turbocharger compressor of a supercharged internal combustion engine and a intake pressure sensor positioned in an intake air distributor.

Advantageously, the first sensor is the atmospheric pressure sensor.

Advantageously, the engine is with spark ignition.

• la figure 1 est une représentation schématique d'un chronogramme du déroulement d'un procédé de recalage selon l'état de la technique, le démarrage ayant réussi, les capteurs de pression étant montrés au-dessus de ce chronogramme tout d'abord selon un premier graphique dans un état non recalé et ensuite selon un second graphique dans un état recalé,
• la figure 2 est une représentation schématique d'un chronogramme du déroulement d'un procédé de recalage selon l'état de la technique, les capteurs de pression étant montrés au-dessus de ce chronogramme tout d'abord selon un premier graphique dans un état non recalé et ensuite selon un second graphique dans un état recalé, le recalage n'ayant pas pu se faire avant le démarrage et le démarrage ayant été suspendu,
• la figure 3 est une représentation schématique de deux gabarits d'erreur pour respectivement un capteur de pression atmosphérique et un capteur de suralimentation, la compensation de recalage n'étant pas ajustée en fonction de la température,
• la figure 4 illustre un logigramme du procédé de recalage selon l'état de la technique tandis que la figure 5 illustre un logigramme du procédé de recalage selon la présente invention.

Other characteristics, aims and advantages of the present invention will appear on reading the detailed description which follows and with regard to the appended drawings given by way of nonlimiting examples and in which:

• the figure 1 is a schematic representation of a timing diagram of the progress of a registration process according to the state of the art, the start having been successful, the pressure sensors being shown above this timing diagram firstly according to a first graph in a non-readjusted state and then according to a second graph in a readjusted state,
• the figure 2 is a schematic representation of a chronogram of the progress of a registration process according to the state of the art, the pressure sensors being shown above this chronogram first of all according to a first graph in a non-readjusted state and then according to a second graph in a state failed, resetting could not be done before starting and starting having been suspended,
• the figure 3 is a schematic representation of two error templates for an atmospheric pressure sensor and a supercharging sensor, respectively, the compensation for adjustment is not adjusted as a function of the temperature,
• the figure 4 illustrates a flow diagram of the registration process according to the state of the art while the figure 5 illustrates a flow diagram of the registration method according to the present invention.

It should be borne in mind that the figures are given by way of examples and are not limitative of the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention.

In what follows, reference is made to all the figures taken in combination. When reference is made to one or more specific figures, these figures are to be taken in combination with the other figures for the recognition of the designated numerical references.

The Figures 1 to 3 have already been detailed in the introductory part of this request.

With reference to the figures, and in particular to the figure 5 , the present invention relates to a readjustment process of at least two Capatm, Capsural, Capadmi pressure sensors positioned in an air intake line of an internal combustion engine.

In this method, said at least two Capatm, Capsural, Capadmi pressure sensors are readjusted by a compensation of Cr (T1) or Cr (T) readjustment calculated for at least a second Capsural, Capadmi sensor compared to a first Capatm sensor of pressure serving as a reference sensor between their respective pressure measurements at a so-called initial temperature of the sensors when the engine is stopped.

This compensation for registration Cr (T1) or Cr (T) is then applied to said at least one second Capsural sensor, Capadmi for correction of its pressure measurements.

According to the invention, an internal diagnostic step is carried out prior to the application of the compensation compensation for said at least one second sensor. on the value of the adjustment compensation consisting in determining whether the adjustment compensation exceeds a maximum compensation value.

If the registration compensation exceeds a maximum compensation value, it is diagnosed that one of said at least two sensors is faulty and, in this case, the application of registration compensation is suspended.

Advantageously, the maximum compensation value Crmax (T), Crmax (T1) can be specific to the pair or to each pair formed by said at least two sensors Capatm, Capsural, Capadmi, the maximum compensation value Crmax (T), Crmax (T1) being greater than 20 or 30 millibars.

Advantageously, a respective error template as a function of the temperature of the Capatm, Capsural, Capadmi sensor can be produced for each sensor, the error template of each Capatm, Capsural, Capadmi sensor defining an error range for each temperature. The compensation compensation Cr (T1) or Cr (T) can then be calculated from the difference of the respective pressure measurements of said at least two Capatm, Capsural, Capadmi sensors at the initial temperature.

After application of the Cr (T1) or Cr (T) registration compensation on said at least one second Capsural sensor, Capadmi, a predetermined time interval may be expected sufficient to carry out a verification that the state of said at least two sensors Capatm, Capsural, Capadmi allows them to perform a consistent pressure measurement.

If it is found that a Capatm, Capsural, Capadmi sensor is not in a position to carry out a coherent pressure measurement, the application of the compensation of registration Cr (T1) or Cr (T) can be canceled. The predetermined time interval can be approximately two seconds.

The invention relates to a powertrain comprising an internal combustion engine with an air intake line to the engine, the line comprising a first and at least a second Capsural, Capadmi pressure sensor. In this powertrain, said at least one second Capural sensor, Capadmi pressure is reset relative to the first Capatm pressure sensor according to a registration process as described above.

As generally present in an air intake line to a turbocharged internal combustion engine with an intake air distributor, the first capatm and said at least one second Capsural pressure sensor, Capadmi pressure can be selected from a Capatm atmospheric pressure sensor, a Capsural boost sensor positioned downstream of a supercharged internal combustion engine turbocharger compressor and a pressure sensor d Capadmi intake positioned in an intake air distributor.

It may for example have only a Capatm atmospheric pressure sensor and a Capadmi air intake sensor in the case of a non-turbocharged engine. Other pressure sensors can also be taken into account.

The first sensor in the sense of the present invention can be the Capatm atmospheric pressure sensor, this being the most precise and the internal combustion engine can be with spark ignition.

The figure 4 shows a flow diagram of a method for resetting pressure sensors present in the air intake line of an internal combustion engine, this method being in accordance with the state of the art, while referring to the other figures for references not indicated in this figure.

This registration process includes the step of turning on or awakening the computer referenced 1 to the figure 4 . This is done as soon as the electrical contact is made for the motor vehicle. From this ignition, a timer T elapses allowing the pressure sensors to readjust as it can be seen in the Figures 1 and 2 .

The readjustment of the pressure sensors by calculating the differences between the values measured by the various sensors is referenced 2 in the figure 4 . Registration compensation, previously referenced Cr (T) or Cr (T1) at the figure 3 , is thus calculated for each pressure sensor with respect to a reference sensor which is advantageously the Capatm atmospheric pressure sensor.

The registration is then applied during a step referenced 3a. This registration is done without internal diagnosis. Then, if a failure is detected, during the next step referenced 4, the engine start is suspended or if no failure is detected, the engine is started. No updating of the compensation compensation with respect to the temperature of the sensors which may vary is provided for in this registration process according to the state of the art.

With reference to the figures and in particular to the figure 5 , the registration process according to the present invention retains the steps referenced 1 and 2 above mentioned, respectively concerning the ignition of the computer, that is to say its awakening by its power-up, and the recalibration calculations for the pressure sensors relative to a reference sensor. The inventive contribution lies in the management of the authorizations for this registration.

The registration process according to the invention begins with the power-up of the computer in charge of the process. A first so-called delay time T is launched as soon as the computer is powered up. As for the state of the art shown in figure 4 , this delay time T has the role of ensuring the balance of the pressures in the air line and that the sensors are in the state to carry out a coherent measurement. Starting or starting the engine interrupts this time delay.

During this time delay, the procedure referenced 2 to figure 5 with calculation of the Cr (T1) or Cr (T) registration compensations between the pressure sensors, this step also forming part of the registration method according to the prior art.

The step referenced 3 of the registration process according to the present invention relates to an internal diagnosis. The role of internal diagnostics is to determine whether one of the sensors detects an atmospheric pressure measurement very far from the pressure measurement of the other or the other sensors.

To do this, we use the offset compensation values Cr (T1) or Cr (T) previously calculated and compare them to a threshold. If these values are above a threshold, then it means that one of the sensors has failed. This step is done with the engine stopped.

Thus, prior to the application of the compensation compensation to a pressure sensor, an internal diagnostic step is based on the value of the compensation compensation consisting in determining whether the compensation compensation Cr (T1) or Cr (T) exceeds a maximum compensation value Crmax (T), Crmax (T1), this internal diagnostic step being referenced 5 at the figure 5 .

In this case, it is diagnosed that the sensor is faulty and, in this case, the application of the compensation for registration is suspended. This makes it possible not to readjust the sensors to inconsistent values.

In the preferred embodiment of the present invention, there may be three pressure sensors in the air intake line to the engine. The registration is then done on at least three Capatm, Capsural, Capadmi pressure sensors with a first reference Capatm sensor among said at least three Capatm, Capsural, Capadmi sensors. It is possible to determine which pressure sensor is faulty among the three, the reference sensor being able to be as well as a failed sensor.

If the Cr (T1) or Cr (T) readjustment compensations between the first Capatm sensor, i.e. the reference sensor and the second and third Capsural sensors respectively, Capadmi both exceed the maximum compensation value Crmax (T), Crmax (T1), it is diagnosed that the first Capatm sensor has failed.

Conversely, if the Cr (T1) or Cr (T) compensation compensation of the first Capatm sensor exceeds the maximum compensation value Crmax (T), Crmax (T1) with one of the second and third Capsural sensors, Capadmi while it does not exceed the maximum value with the other of the second or third sensors, it is diagnosed that the second or the third Capsural sensor, Capadmi associated with a Cr (T1) or Cr (T) registration compensation exceeding the compensation value maximum Crmax (T), Crmax (T1) is faulty.

Reference 6 to the figure 5 indicates the step for measuring the sensor temperatures. If the temperatures of the sensors go beyond a certain threshold, for example by leaving the temperature interval between 0 and 85 ° C. then the initial compensation compensation Cr (T1) or Cr (T) is suspended.

It can indeed be seen with regard to the figure 3 that below and above this interval, the precision interval of each Capatm, Capsural, Capadmi sensor increases suddenly, which leads to a degradation of the precision of each Capatm, Capsural, Capadmi sensor.

If all the conditions are fulfilled, namely mainly a pressure measurement temperature in the interval and no outlier given by at least one sensor, at the end of the time delay T, the sensor (s) are reset pressure relative to one of the pressure sensors then being the reference sensor. This step is referenced 3 to the figure 5 . Only one of these two temperature or outlier conditions is sufficient to suspend registration.

However, a variable of a complete diagnosis is expected for each Capatm, Capsural, Capadmi sensor for a period of time following registration. referenced 3 to the figure 5 . Despite the internal diagnostic step referenced 5, it is important to take into account the diagnosis of the sensors. Indeed, the internal diagnosis is effective in avoiding inconsistent readjustments on erroneous values, but it is much less complete than this complete and external diagnosis for each sensor. The complete diagnostic time D for each sensor begins when the computer is switched on and continues longer than the time delay T, for example exceeding two seconds.

As a result, failures may not have been diagnosed during the internal diagnostic step 5 whereas these failures may be signaled by a complete sensor diagnosis. Thus, for a period after registration, of approximately two seconds, the verification step is carried out if a diagnostic variable for each sensor reveals a failure of the respective Capatm, Capsural, Capadmi sensor, this by a complete and external diagnosis to the sensors. In this case, the registration carried out in step 3 is canceled. This verification and cancellation or confirmation step is referenced 4 to the figure 5 .

This operation is done after resetting since it cannot be done before due to too long a duration for the completion of the complete diagnosis on the sensors. Given the arrival time of the complete sensor diagnostic variable, incompatible with the need to quickly reset the sensors, the registration takes place before any detection and confirmation of a fault but can be revised later by being canceled.

The complete diagnosis on the sensors only arrives after a certain period after registration. This period is of the order of 2 seconds. However, if a sensor fault is noted by the complete diagnosis of the sensors, this fault is taken into account to cancel the registration.

To the figure 5 , the cancellation step or the confirmation step of registration is referenced 7. After the cancellation step, the sensors keep their original value while the registration is confirmed if no fault on the sensors is found.

Claims (10)

1. A method for resetting at least two pressure sensors (Capatm, Capsural, Capadmi) positioned in an air-intake line of an internal combustion engine, in which said at least two pressure sensors (Capatm, Capsural, Capadmi) are reset by a resetting compensation (Cr(T1) or Cr(T)) calculated for at least one second sensor (Capsural, Capadmi) with respect to a first pressure sensor (Capatm) serving as reference sensor between their respective pressure measurements at a temperature designated as initial temperature of the sensors when the engine is stopped, this resetting compensation (Cr(T1) or Cr(T)) being then applied to said at least one second sensor (Capsural, Capadmi) for correction of its pressure measurements, characterized in that there is carried out, prior to the application of the resetting compensation (Cr(T1) or Cr(T)) to said at least one second sensor (Capsural, Capadmi), an internal diagnostic step based on the value of the resetting compensation (Cr(T1) or CrT)) consisting of determining whether the resetting compensation (Cr(T1) or Cr(T)) exceeds a maximum compensation value (Crmax(T), Crmax(T1)), in which case it is diagnosed that one of said at least two sensors (Capatm, Capsural, Capadmi) is faulty and in that, in this case, the application of the resetting compensation (Cr(T1) or Cr(T)) is suspended.
2. The method according to Claim 1, in which the resetting is carried out to at least three pressure sensors (Capatm, Capsural, Capadmi) with a first reference sensor (Capatm) among said at least three sensors (Capatm, Capsural, Capadmi) and, if the resetting compensations between the first sensor (Capatm) and respectively the second and third sensors (Capsural, Capadmi) both exceed the maximum compensation value (Crmax(T), Crmax/(T1)), it is diagnosed that the first sensor (Capatm) is faulty, whereas, if the resetting compensation (Cr(T1) or Cr(T)) of the first sensor (Capatm) exceeds the maximum compensation value (CrMax(T), Crmax(T1)) with one of the second and third sensors (Capsural, Capadmi), although it does not exceed the maximum value with the other of the second or third sensors (Capsural, Capadmi), it is diagnosed that the second or the third sensor (Capsural, Capadmi) associated with a resetting compensation (Cr(T1) or Cr(T)) exceeding the maximum compensation value (Crmax(T), Crmax(T1)) is faulty.
3. The method according to any one of Claims 1 or 2, in which the maximum compensation value (Crmax(T), Crmax(T1)) is specific to a pair or to each pair formed by said at least two sensors (Capatm, Capsural, Capadmi), the maximum compensation value (Cmax(T), Crmax(T1)) being greater than 20 or 30 millibars.
4. The method according to any one of the preceding claims, in which a respective error template is developed as a function of the temperature of the sensor (Capatm, Capsural, Capadmi) for each sensor (Capatm, Capsural, Capadmi), the error template of each sensor (Capatm, Capsural, Capadmi) defining a range of error for each temperature, the resetting compensation (Cr(T1) or Cr(T)) being calculated from the difference of the respective pressure measurements of said at least two sensors (Capatm, Capsural, Capadmi) at the initial temperature.
5. The method according to any one of the preceding claims, in which there is carried out, prior to the resetting compensation (Cr), a measurement step of temperature at the level of said at least two sensors (Capatm, Capsural, Capadmi) and if the temperature is not within a predetermined temperature interval, the resetting compensation (Cr(T1) or Cr(T)) is suspended, this interval being from 0 to 85 °C.
6. The resetting method according to any one of the preceding claims, in which , after application of the resetting compensation (Cr(T1) or Cr(T)) to said at least one second sensor (Capsural, Capadmi), there is a wait during a predetermined time interval sufficient to carry out a verification that the status of said at least two sensors (Capatm, Capsural, Capadmi) allows them to carry out a coherent pressure measurement and that if it is found that a sensor (Capatm, Capsural, Capadmi) is not in a state to carry out a coherent pressure measurement, the application of the resetting compensation (Cr(T1) or Cr(T)) is cancelled, this time interval being approximately two seconds.
7. A powertrain including an internal combustion engine with an air-intake line to the engine, the line including a first (Capatm) and at least one second pressure sensor (Capsural, Capadmi), characterized in that said at least one second pressure sensor (Capsural, Capadmi) is reset with respect to the first pressure sensor (Capatm) in accordance with a resetting method according to any one of the preceding claims.
8. The powertrain according to Claim 7, in which the first (Capatm) and said at least one second pressure sensor (Capsural, Capadmi) are selected from an atmospheric pressure sensor (Capatm), a supercharging sensor (Capsural) positioned downstream of a turbocharger compressor of a supercharged internal combustion engine, and an intake pressure sensor (Capadmi) positioned in an intake air distributor.
9. The powertrain according to any one of Claims 7 or 8, in which the first sensor is the atmospheric pressure sensor (Capatm).
10. The powertrain according to any one of Claims 7 to 9, in which the engine is a spark ignition engine.

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