WO2017131568A1

WO2017131568A1 - Fault codes in a motor vehicle

Info

Publication number: WO2017131568A1
Application number: PCT/SE2016/051251
Authority: WO
Inventors: Björn Johansson; Ulf Bergman; Jonas Biteus; Fredrik Pettersson; Rasmus BACKMAN; Per Olsson; Björn MALMGREN
Original assignee: Scania Cv Ab
Priority date: 2016-01-29
Filing date: 2016-12-13
Publication date: 2017-08-03
Also published as: SE1650116A1

Abstract

An electronic control system (1) for a motor vehicle, and a method of monitoring a motor vehicle performed by an electronic control system (1) of the motor vehicle is provided. The method includes detecting (101, 107) faults, registering (102, 108) a fault code in a register upon detecting (101) a fault, which registering includes indicating that the fault is active, and inactivating (103, 109) the fault code in connection with a removal, or disappearance, of the fault. Especially, said monitoring includes registering (102, 108) of fault codes both during use of the motor vehicle and during repair of the motor vehicle, wherein the registering (108) of a fault code during repair includes indicating that the fault appeared during repair. In this way, faults appearing as a consequence of a repair action may be identified in the register and distinguished from faults appearing during use.

Description

Fault Codes in a motor vehicle

Technical Field

The invention relates to an electronic control system for a motor vehicle and a method of mon itoring a motor vehicle. Especially, the electronic control system and the method relates to the reg istration of fault codes in such an electron ic control system .

Background

It has become common to util ize electron ic control systems in modern land motor vehicles in order to control the function ing of the motor vehicle and its equ ipment. The electronic control system controls devices and systems of the motor vehicle, and may for example control devices and systems such as the electric system , eng ine, transmission line, braking system , gearbox, combustion system , navigation system , safety features, driver utilities etc. The electronic control system often includes a comm unication bus that comm unicatively intercon nect electronic control un its (ECUs) of the electron ic control system , which ECUs are fu rther con nected to sensors, measurement devices and components of the motor vehicle. Such electronic control systems utilize measurements and status indications for controlling the functions of the motor vehicle and its components. One function of the electron ic control system is to detect faults or malfunctions of the motor veh icle, components and equipment, wherein the electron ic control system detects faults and perform safety functions in the motor vehicle. The present invention relates to the storing of fault codes in an electronic control system of a land motor vehicle, such as a car, a truck or a bus. Known electron ic control systems monitor the function ing of components of the vehicle and generate and store fau lt codes when something is malfunctioning . The fault codes may be used by a safety system of the electronic control system for performi ng safety functions when the motor veh icle is used. The fau lt codes may also be retrieved and used by a mechan ic in a workshop for performing a diagnosis of the motor vehicle in order to repair the motor vehicle. The US patent docu ment US 2008/01 61 994 (^'994) briefly describes some electronic control systems that uses fault codes (see §0003-§0009 in ^'994) . Such electron ic control systems is provided to generate and store fault codes in a table format, and the fault codes may be read out by means of external computer devices upon repairi ng a faulty veh icle. The docu ment ^'994 especially concerns generating a table of fault codes in a hu manly readable format, see §001 0 of ^'994, which table is presented on a service tool . A fault condition status is indicated as a flag at each fau lt code, see §001 7, §001 9 in ^'994. The electronic control system controls the vehicle on the basis of the fau lts when the fau lts appear. After service, the system may be reset, see §0021 in ^'994.

By deleting a flag that indicates that a fault code is active, the table wil l indicate that the fault code has been deactivated , i .e. a fault of the motor vehicle has been repai red. However, duri ng repair or service of the motor vehicle, ECUs, components or other parts of the motor vehicle may be removed , which may lead to the generation of fu rther fault codes. These fau lt codes wil l then indicate that something has been malfunction ing and subsequently been repaired even though there actually was no fau lt of the motor vehicle, since the fau lt codes only appeared as a consequence of a repairi ng or service action . Indications of earlier faults, such as fau lt codes created during service or repair, may be interpreted during a fol lowi ng service or repair as an indication of an earlier fault of the motor vehicle. These indications may lead a mechanic to believe some component has been malfunctioning , or may make diag nosis of the motor veh icle more difficult, and may lead to unnecessary replacement of fu lly operable components of the motor vehicle. Summary of invention

An aim of the present invention is to remove or at least alleviate the shortcomings of the prior art. In a first aspect, the present invention provides an electronic control system for a motor veh icle. The electronic control system comprises a controller, at least one electronic control unit, at least one sensor, and a comm unication means connecting said electronic control unit and/or said sensor to the controller wherei n the electronic control system is configured to transfer information indicative of fau lts of the motor veh icle from said electron ic control unit and/or said sensor to the controller, and wherein the controller comprises a register for registering fau lt codes indicative of faults and is config ured to register a fault code together with a status of the corresponding fault wh ich status i ndicates that the fault is either active or inactive. Especially, the controller is further config ured to indicate in said reg ister whether a fault code is registered during repair of the motor vehicle.

Such a registration is valuable since fault codes generated du ring a repair or service of the motor veh icle may not relate to an actual fau lt, but may be initiated by a normal repair or service action . By performing registration of fault codes also during repair, the fau lt codes can be used for safety purposes during the repair. Safety functions that rely on fau lt codes and that are already present in the electron ic control system may continue to function properly. In an embodiment of the first aspect, the electronic control system comprises means for commun icative connection to an external computer device, for example a device for displaying the fault codes to a mechanic, wherein the control ler is configu red to enter a repai r mode upon con nection to the external computer device, which repair mode comprises reg istering fault codes as registered duri ng repair. Preferably, the controller is configured to exit the repair mode upon disconnection from the external computer device, and subsequently register fault codes without indicating repair of the motor vehicle.

In an embodiment of the first aspect the electron ic control system comprises means for performing safety functions based on the fault codes, wh ich means for performing safety actions are kept active during the repair mode.

In an embodiment of the first aspect, the electronic control system is configu red for manual deactivation of at least one of the fault codes and/or to automatically deactivate at least one of the fau lt codes following a function test.

According to a second aspect, the present invention provides a method of monitoring a motor vehicle, which method is performed by an electronic control system of the motor vehicle. The method comprises:

- detecting faults,

- registering a fau lt code in a register upon detecting a fau lt, wh ich reg istering i ncludes indicating that the fau lt is active.

The method further comprises inactivating the fault code in con nection with a removal , or disappearance, of the fault. Especially, said method of monitoring comprises performi ng the reg istering of fau lt codes both du ring use of the motor vehicle and duri ng repair of the motor vehicle, wherein the registering of a fault code du ring repair incl udes indicating that the fault appeared du ring repair.

An embodiment of the second aspect, includes :

- detecti ng con nection , and disconnection , of the electron ic control system to, and from , an external computer device,

- entering a repair mode upon detecting connection to the external computing device, and - exiting the repair mode upon detecting disconnection from the external computing device, in order to determine when repair is performed and i ndicate that the fault code appeared during repair.

The method may alternatively, or additionally, allow man ual transfer between a fi rst and second mode of operation , i .e. to and from the repair mode, performed for example by a mechanic at a workshop.

In an embodiment of the second aspect, the inactivating of at least one fau lt code, of the fau lt codes, is performed upon perform ing a functioning test and/or upon receiving a manual input from a user.

Brief Description of the Drawings

The invention will now be described in exemplary embodiments with reference to the accompanying drawings, wherein :

Fig ure 1 il lustrates an embodiment of parts of an electron ic control system 1 of a motor vehicle for the purposes of faci litati ng implementation the present invention ;

Fig ure 2 is a table illustrating a fau lt code register in accordance with an embodiment of the present invention ;

Fig ure 3 is a flow chart illustrating an embodiment of monitoring and registering actions performed in accordance with the present invention .

Fig ure 4 is a flow chart i llustrating a further embodiment of the embodiment of figu re 3. Detailed Description

Fig ure 1 illustrates an embodiment of a part of an electron ic control system 1 for a motor vehicle, especial ly a land motor veh icle (not illustrated) . The electronic control system 1 comprises a controller 2, a number of electronic control u nits, ECUs, 3, sensors 4, electronic components 5 and a commun ication bus 6. The controller 2 is com municatively connected by means of the com munication bus 6 to each ECU 3. Each ECU is connected to one or more sensor 4 and/or a component 5. The controller 2 may also be directly con nected to a sensor 4. An ECU 3 may for example be provided for controlling a specific device or system , such as the gear box or the braking system , and may be connected to all the components 5 of the specific device or system and the sensors 4 arranged at that specific device or system . The controller 2 in the illustrated embodiment of figure 1 is also connected to a commun ication means 7 for com municating with an external computer device 1 0 , such as a PC used at a workshop used for diagnosis, service and repair of the motor vehicle. The com mun ication means 7 may be a physical contact for cable connection to the external computer device, but may alternatively be, or also include, a wireless com mu nication u nit.

The controller 2 comprises a register 21 for registering faults and is config ured to receive fault codes from the other devices, especially the ECUs 3 and register the fault codes in the register 21 . The controller 2 may also be configu red to create fault codes by determin ing , e.g . from information received from the ECUs 3 and/or sensors 4, that one or more components 5 of the motor vehicle is malfunction ing . The controller 2 also includes means 22 for performing safety actions, which means 22 for perform ing safety actions is config ured to take action based on fau lts that occur, as indicated by the fau lt codes in the register 21 . The controller 2 may for example be provided as an electron ic control u nit, and the reg ister 21 and the means 22 for perform ing safety actions may be provided as software for controlling the electron ic control unit, i .e. the controller 2. In the illustrated embodi ment, the means 22 for performing safety actions is i llustrated as a single unit with in the controller 2, but the fu nctions of the means 22 for performing safety actions may however be distributed among several ECUs 3 of the electron ic control system 1 . For example an ECU controlling the gear box may be provided with safety function not allowing gear sh ift selections i n response to a specific fau lt code, or an ECU 3 controll ing an internal combustion engine may be provide with safety functions to not allow start of the engine in response to one or more specific fault codes stored in the register 21 .

The controller 2 is configured to detect connection to the external computer device 1 0, and configured to store fault codes in the reg ister 21 i n differi ng ways in view of the electronic control system 1 being connected to the external computer device 1 0 or not. The controller 2 is configured to register fault codes i n the register 21 in accordance with a first mode when the electronic control system 1 is not connected to the external computer device 1 0 and in accordance with a second mode, a repair mode, when the electronic control system 1 is con nected and commun icates with the external computer device 1 0. Upon connecting an external computer device 1 0 the controller 2 may be configured to perform a handshake action , such as includi ng an indication of identity and/or an indication of repai r. The connection may be configu red for automatic transfer of a repair indication from an external computer device 1 0 of a workshop to the controller 2, and/or the controller 2 may be configured for receiving a repair mode signal that is manually in itiated by a mechanic. Fig ure 2 ill ustrates an embodiment of the reg ister 21 of the controller 2. The register 21 is il lustrated in table format, wherein the fi rst colu mn is utilized by the controller 2 for entering a fau lt code for each occurring fau lt. The second column is used by the controller 2 to indicate whether the fault is active or not, i .e. the status of the fault. Thus, when a fault occur the controller 2 reg isters the fault code of the fau lt in the first colu mn and i ndicates that the fault is active in the second column , e.g . flagg ing the fault code by a status indication such as a "1 ". When the fault disappears, e.g . a faulty component is repaired or exchanged, the controller 2 is configured to inactivate the fault code by changing the status in column 2, for example from a "1 " to a "0".

The table illustrating the register 21 also includes a third column provided for registering whether the fault appeared during repair or not, and the controller 2 is configured to indicate whether the fault appeared during repair of not in the register 21 by means of setting a flag, for example "1" when registering a fault code during repair and with a "0" when registering a fault code during use of the motor vehicle, i.e. when not connected to an external computer device 10. The controller 2 may be configured to not alter the repair mode indication when the fault disappears, merely deactivate the fault code, and is thus configured to permanently store the repair mode indication in the register 21. The indication of a repair mode gives valuable information to service and repair personnel, and by keeping the fault code registration active during repair also enables the safety actions performed by the means 22 for performing safety actions active during a repair or service. Thus, the electronic control system 1 can be allowed to continue functioning as when the motor vehicle is in use also during repair, and fault codes reflecting repair rather than faults can be easily identified in the register 21. The controller 2 may be configured to delete fault codes upon receiving a command for deleting fault codes, especially fault codes indicated during the repair mode.

Figure 3 illustrates an embodiment of the monitoring and registering functions of the controller 2 of the electronic control system 1 of figure 1 as a flow chart. The controller 2 is provided to detect faults 101, 107, register 102, 108 fault codes in the register 21, and inactivate fault codes 103, 109 in the register, e.g. changing the status flag from active, "1", to inactive, "0". The controller 2 is also configured to change (104, 110) from the first operating mode to the second operating mode, i.e. the repair mode, upon determining 104 that the electronic control system is connected to the external computer device 10 and upon determining 110 that the electronic control system 1 is disconnected from the external computer device 10, respectively. The functions of detecting 101, 107, registering 102, 108 and inactivating 103, 108 is performed continuously through the monitoring process 100, and is only illustrated as steps performed in specific order for illustrative purposes of understanding the invention. The steps of determining connection 104 and disconnection 110, wherein the operating mode is changed between the first mode and the second repair mode affects how the controller 2 performs the steps of registration 102, 108.

The illustrated method of monitoring 100 the motor vehicle includes detecting, or determining, a fault. Registering 102 the fault by means of entering a fault code in the register 21 together with a status indication, indicating active, and indicating that the fault did not appear during repair or service. The method further includes inactivating 103 a fault code by changing status from active to inactive when a fault disappear. The method further includes determining 104 if the motor vehicle is being connected to an external computer device 10, and if so entering 105 the second mode, i.e. the repair mode. The repair mode includes communicating 106 with the external computer device 10, especially transferring the register 21 to the external computer device 10, and continuing to detect 107 faults, register faults 108 and inactivate 109 fault codes when the faults are removed during the repair. The step of registering 108 fault codes performed in the repair mode includes indicating in the register 21 that the fault appeared during repair, as exemplified by indicating a "1" in the register 21 in accordance with the table of figure 2. The repair mode of the monitoring method 100 also includes determining 110 when the motor vehicle becomes disconnected from the external computer device 10 whereupon the method includes exiting 111 the repair mode and returning to detecting faults 101, registering faults 102 and inactivating fault codes 103 and monitoring the connection to the external computer device in accordance with the first operating mode. Otherwise, the repair mode continues with communicating 106 with the external computer device, detecting/determining faults 107, registering 108 fault code including status active and during repair, and with inactivating 109 faults that disappear or are removed during the repair.

The inactivation 103, 109 of fault codes may be subjected to requirements or restrictions in a variety of ways. The controller 2 may be configured for both manual and automatic inactivation 103, 109 of fault codes. The controller 2 may be configured to only allow inactivation of some, and not all, faults following performance of a function test. Thus, for some faults, the controller 2 may be configured to allow manual inactivation of a fault code only after performance of a successful function test of the system or component in question. The controller 2 may also be configured for automatic inactivation of some fault codes following a successful function test. Upon exiting 111 the repair mode, the method may include a step of clearing 112 fault codes or fault code status indications. For example, the controller 2 may be configured to clear 112 fault codes that appeared during repair and that are inactive during exiting 111 of the repair mode. Furthermore, the controller 2 may be configured for clearing fault code indications, so that the step of clearing 112 includes clearing repair mode indication for faults that are still active after the repair. Figure 4 illustrate a further embodiment of the method of figure 3, wherein upon connection 104 of an external computer device 10 the method includes a step of selecting 114 whether or not to enter the repair mode. Such a selection 114 step is valuable, since for example a mechanic or service personnel may connect the electronic control system 1 of the motor to an external computer device 10 in order to perform one or more function tests of the motor vehicle. Thus, the external computer device 10 may be connected in order to collect data during a test in order to perform a diagnosis, or in order to test, such as drive, the motor vehicle after a repair. The embodiment of figure 4 illustrates similar steps of the repair mode as in figure 3, including entering 105 repair mode, communicating 106 fault codes, detecting 107 faults, registering 108 fault codes with a repair indication, inactivating 109 fault codes upon repair, exiting 111 repair mode, and clearing 112 fault codes and/or fault code 112 indications. The repair mode of figure 4 includes an additional step of selectively exiting 115 repair mode and entering a third mode of operation when connected to an external computer device 10. The third mode of operation is exemplified as a test mode, during which third mode the electronic control system 1 of the motor vehicle is connected to an external computer device. Exiting 115 the repair mode may be performed upon receiving a command initiated from a user, e.g. mechanic. The third mode includes communicating 116 fault codes, upon entering, and may repeat this step 116 automatically or upon command from the external computer device 10, e.g. as controlled by the mechanic. The step of communicating 116 fault codes in the third mode is similar or identical to the step of communicating 106 fault codes in the repair mode/second mode. The third mode also includes detecting faults 117, registering faults 118, an inactivating 119 faults, which steps may be performed in the same way as the detection of faults 101, the registration of faults 102, and inactivating 103 of faults performed during use, i.e. in the first mode. The difference from normal use being the communicating 116 of fault codes to the external computer device and the step of selective entering 114 into the repair mode without disconnecting (step 120) from the external computer device 10 and the returning to the first mode upon disconnection, step 120, from the external computer device. Thus, the test mode or third mode includes a step of determining 120 disconnection from the external computer device. If not disconnected, the third mode is repeated, but may selectively enter 114 the repair mode. If disconnection is determined 120, the third mode may include a step of clearing 112, e.g. clearing inactive fault codes for faults appearing during repair, or clearing repair mode indication for faults still active after disconnection 120 from the external computer device. After disconnection, the electronic control system returns to the first mode of operation, i.e. the method of monitoring continues in the first mode.

The controller 2 may also be configured to inactivate some fault codes after manual instructions from a user, such as a mechanic, without performance of a function test. Thus, the controller 2 may be adapted for a variety of further control functions regarding inactivation of fault codes without deviating from the scope of the present invention. The selection of which fault codes that should require function tests, or not, should be the object of manual and/or automatic removal is however not a specific feature of the present invention.

An electronic control system (1) for a motor vehicle, and a method of monitoring a motor vehicle performed by an electronic control system (1) of the motor vehicle has been provided in embodiments. The method includes detecting (101, 107) faults, registering (102, 108) a fault code in a register upon detecting (101) a fault, which registering includes indicating that the fault is active, and inactivating (103, 109) the fault code in connection with a removal, or disappearance, of the fault. Especially, said monitoring includes registering (102, 108) of fault codes both during use of the motor vehicle and during repair of the motor vehicle, wherein the registering (108) of a fault code during repair includes indicating that the fault appeared during repair. In this way, faults appearing as a consequence of a repair action may be identified in the register and distinguished from faults appearing during use. The present invention is however not restricted to these embodiments but may be varied within the scope of the claims.

The fu nctions of the electron ic control system and the monitoring method described, of figu res 1 to 4, may be provided by means of a computer-readable media, such as a computer program product i nstallable in an electron ic control system 1 of a motor vehicle. Such a computer program product may be provided in a non-transitory memory, such as a computer disc, a hard disc or a flash memory. The computer prog ram product may be transferred from a first non-transitory memory to a second non-transitory memory, which second non-transitory memory is provided i n an electronic control system of a motor vehicle, and wh ich transfer may include a transitory signal , such as a signal transferred by means of Internet, a cable and/or a wireless connection . The expression "non-transitory" computer- readable media should be i nterpreted as all computer-readable media, with the sole exception being a transitory, or propagating , signal .

Figure 5 il lustrate a first non-transitory memory 51 , and a second non-transitory memory 52 of a motor vehicle wherein a computer program product 55 stored in the first non-transitory memory 51 is transferred via Internet 53 to, and stored in , the second non-transitory memory 52. Fig ure 5 also illustrate a computer program product 55 for providing the present invention , which is stored in a computer disc 54. The computer program 55 of the computer disc 54 may be transferred directly to the electron ic control system 1 or via an external computer device 1 0.

The present invention primarily concerns land motor vehicles, such as cars, buses, trucks, motor cycles, but may also be implemented i n other motor veh icles, such as boats, ships or for example airplanes.

Claims

1. Electronic control system (1) for a motor vehicle comprising a controller (2), at least one electronic control unit (3), at least one sensor (4), and a communication means (6) connecting said electronic control unit (3) and/or said sensor (4) to the controller (2), wherein the electronic control system (1) is configured to transfer information indicative of faults of the motor vehicle from said electronic control unit (3) and/or said sensor (4) to the controller (2), and wherein the controller (2) comprises a register (21) for registering fault codes indicative of faults and is configured to register a fault code together with a status of a corresponding fault which status indicates that the fault is either active or inactive, c h a r a c t e r i z e d in that the controller (2) is further configured to indicate in said register (21) whether a fault code is registered during repair of the motor vehicle.

2. Electronic control system according to claim 1, wherein the electronic control system (1) comprises means (7) for communicative connection to an external computer device (10), wherein the controller (2) is configured to enter a repair mode upon connection to the external computer device (10), which repair mode comprises registering fault codes as registered during repair.

3. Electronic control system according to claim 2, wherein the controller (2) is configured to exit the repair mode upon disconnection from the external computer device (10), and subsequently register fault codes without indicating repair of the motor vehicle.

4. Electronic control system according to any of claims 1 to 3, wherein the electronic control system (1) comprises means (22) for performing safety functions based on the fault codes, which means for performing safety actions are kept active during the repair mode.

5. Electronic control system according to any of claims 1 to 4, wherein the electronic control system (1) is configured for manual deactivation of at least one of the fault codes and/or to automatically deactivate at least one of the fault codes following a function test.

6. A method of monitoring a motor vehicle performed by an electronic control system (1) of the motor vehicle, said method comprising:

- detecting (101 , 107) faults,

- registering (102, 108) a fault code in a register upon detecting (101) a fault, which registering includes indicating that the fault is active, and wherein the method further comprises:

- inactivating (103, 109) the fault code in connection with a removal, or disappearance, of the fault, said method of monitoring is c h a r a c t e r i z e d in performing the registering (102, 108) of fault codes both during use of the motor vehicle and during repair of the motor vehicle, wherein the registering (108) of a fault code during repair includes indicating that the fault appeared during repair.

7. A method of monitoring a motor vehicle according to claim

6, including:

- detecting connection (104), and disconnection (110), of the electronic control system (1) to, and from, an external computer device (10),

- entering (105) a repair mode upon detecting connection (104) to the external computing device (10), and

- exiting (111) the repair mode upon detecting disconnection (108) from the external computing device (10), in order to determine when repair is performed and indicate that the fault code appeared during repair.

8. A method of monitoring a motor vehicle according to claim 6 or 7, wherein inactivating (103, 109) of at least one of the fault codes is performed upon performing a functioning test and/or upon receiving a manual input from a user.

9. A motor vehicle comprising an electronic control system (1) in accordance with any of claims 1 to 5, and/or comprising an electronic control system configured to perform the method according to any of claims 6 to 8.

10. A computer program (55) which when executed by an electronic control system 1 of a motor vehicle enables the electronic control system to perform the method of monitoring according to any of claims 6 to 9.

11. A computer program product (54) comprising a computer program in accordance with claim 10, which computer program (55) is stored in a non-transitory memory (54).

12. Method of installing a computer program (55) in accordance with claim 10 in an electronic control system 1 of a motor vehicle comprising transferring the computer program (55) from a non-transitory memory (51, 54) located outside the motor vehicle into a non-transitory memory (52) located in the electronic control system 1.