Process and apparatus for diagnosis of defects in electric or electronic modules in automotive vehicles

• US 5,107,428 A
• Filed: 12/22/1989
• Issued: 04/21/1992
• Est. Priority Date: 12/22/1988
• Status: Expired due to Fees

• Current Assignee: ACTIA SA (Actia Group)
• Original Assignee: ACTIA SA (Actia Group)
• Inventors: Fonte, Jean-Claude, Bethencourt, Gilles
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US07/456,091
• Time in Patent Office: 851 Days
• Field of Search: 364/424.03, 364/424.04, 364/431.01, 364/551.01, 73/116, 73/117.2, 73/117.3, 73/119 R, 371/16.1
• US Class Current: 701/35
• CPC Class Codes: G01R 31/007 using microprocessors or computers
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005

Abstract

The invention relates to a process and an apparatus for diagnosing defects in electric or electronic modules mounted in an automotive vehicle. This apparatus comprises a wire harness (2) adapted to divert status or control signals from a system to be tested, a formatting interface (15) comprising a plurality of calibrating modules arranged in parallel, a multiprocessor (21) connected to the formatting interface (15) and comprising a backup memory in which are stored, in real time, the defect signals, memories (25) for storage of a set of diagnostic programs corresponding to a group of systems to be tested, adapted to configure the multiprocessor (21) in such a manner as to dedicate it to the treatment of signals from a given system, and a man/machine interface (28) having means for displaying the contents of the backup memory and manual selection means.

Claims

1. A process for diagnosing defects in electric or electronic modules mounted on automotive vehicles, said modules being of the type receiving electric status signals characteristic of the static and dynamic state of components of the vehicle and generating electric control signals for controlling said modules, said status and control signals being representative at each moment of a set of specific operation parameters of the vehicle, said process comprising:

preliminarily storing in storage memories diagnostic programs corresponding to each type of system to be tested, and a set of default thresholds related to each operating parameter associated with each of said diagnostic programs for each of said systems,

continuously comparing the status and control signals to the limits of the modules of the system to be tested, in such a manner as to continuously arrange said signals in a branch network (2),

simultaneously and in parallel formatting said signals for bringing them into a range of predetermined values and obtaining calibrated signals,

selecting by a manual command the diagnostic program corresponding to the system to be tested, and the associated default thresholds,

configuring a multiprocessor (21) by means of a selected diagnostic program for dedicating it to the treatment of status and control signals specific to the system selected and imposing on one of the status or control signals a priority bit,

digitizing, by means of the configured multiprocessor (21) the calibrated signals and the combinations of said signals over a period related to the priority signal, of a duration lower than that of the period of said priority signal, in such a manner as to generate during said period a set of digital signals representative of the calibrated signals,

storing the digitized signals obtained during each period in a read write memory,

searching said read write memory at each period and calculating in real time a set of values representative of the operating parameters for the period considered,

comparing in real time each calculated value to the default thresholds preliminarily stored and selected for generating a default signal in case of excess,

storing in real time for each value the resulting default signal in a backup memory (42), said backup memory having a first zone with a capacity at least equal to the number of operating parameters,

counting down for each value the number of appearances of the corresponding default signal and storing at least one datum related to this number in a second zone of the backup memory (42), and

displaying the contents of the backup memory as an indicator of deflective conditions of said modules.

2. A diagnostic process as in claim 1 and including configuring the multiprocessor (21) by means of a diagnostic program selected in such a manner as to sequence the set of status and control signals in at least one hierarchal class, while allocating to them, for each class, a predetermined hierarchal weight, and

upon appearance of a default signal on a value of a given class, inhibiting the resulting default signals of values of the same class corresponding to signals of lesser hierarchal weight.

3. A diagnostic process as in claim 2, and including

configuring the multiprocessor (21) in such a manner as to allocate to one of the classes a privilege character,

inhibiting the default signals of the other classes in case of appearance of a default signal in said privileged class.

4. A process as in claim 3 for carrying out a diagnosis on systems of modules associated with at least one rotating member and receiving a speed status signal representative of the speed of rotation of said rotating member and its angular position at each moment, said process further comprising configuring the multiprocessor (21) in such a manner as to allocate a priority character to the speed status signal.

5. A process as in claim 4 for carrying out a diagnosis and wherein said vehicle includes a plurality of modules associated with one or more of the following members:

a battery, an ignition rotor, an ignition coil, an injector, a flowmeter, a relay pump, air and water temperature sensors, a fuel inlet solenoid valve, the process comprising configuring said multiprocessor (21) in such a manner as to order the status and control signals in at least five classes to be arranged in the following order;

a first class having a privilege character comprising signals of battery voltage, signals of weight control,

a second class comprising a speed signal or ignition coil,

a third class comprising a speed signal generated by the ignition rotor, a signal from the pump relay, or a signal from the injector control,

a fourth class comprising signals from the flow meter or air temperature sensors,

a fifth class comprising a solenoid valve signal or a water temperature sensor signal.

6. A diagnostic process as in claim 1 comprising:

preliminarily displaying the contents of the backup memory (42), selecting a predetermined combination of information to be displayed from a set of combinations corresponding to different types of diagnoses, and

displaying only the selected combination of information.

7. A diagnostic process as in claim 6, comprising selecting the diagnostic probram of the system to be tested and the combination of information to be displayed;

generating the successive display of menus bearing indications representative of the stored types of systems to be tested and the set of combinations to be displayed,

actuating a cursor for choosing indications contained in the menu.

8. A diagnostic process as in claim 6, displaying in real time at least one fraction of the read write memory for visualizing the value of the operating parameters.

9. A diagnostic process as in claim 1 comprising:

storing in a storage memory a table of aids to the repair comprising for each default signal, information for helping the repair,

displaying on request the information from this table which corresponds to a default signal when the status signal is displayed.

10. A diagnostic process as in claim 1 comprising:

imposing on each wiring harness (2) to a system to be tested an electric parameter for identifying the system to be tested,

providing each diagnostic program with a code representative of the electric parameter of the system to be tested to which the diagnostic program corresponds, and

thereafter verifying the concordance of the code and of the electric parameter to either proceed with the diagnosis in case of concordance, or to prevent the diagnosis in case of non-concordance.

11. A diagnostic process as in claim 1 comprising, for each period, digitizing the set of calibrated signals to be carried out in parallel.

12. A diagnostic apparatus for comprising in combination:

a set of wire harnesses (2) comprising at one end a standard connector (2a) and at the other end a branch connector (3) adapted to branch to the terminals of modules of a system to be tested for delivering status and control signals,

a formatting interface (15) having input connectors (16) corresponding to said standard connectors (2a), said interface comprising a plurality of calibrating modules (29, 30,

     31) having their inputs arranged in parallel,

a multiprocessor (21) connected to the formatting interface (15) and comprising a plurality of counters and analog/digital converters, at least two processors (39,

     40) organized as master/slave, a read write memory for storing in real time the digital signals obtained, and a backup memory (42) for storing defect signals and data associated with said defect signals,

memory means for storing a set of diagnostic programs corresponding to a set of systems to be tested, said memory means being connected to the multiprocessor (21),

connection means (28;

14, 46;

     47) adapted to connect the multiprocessor (21) with a man/machine interface having display means and manual selection means,

electric feed means (43) provided with a connector for attachment to a battery (44) of an automotive vehicle, said means being adapted to convert the battery voltage to an appropriate regulated voltage for feeding to the apparatus.

13. A diagnostic apparatus as in claim 12, characterized in that the formatting interface comprises an interchangeable card (15) having a plug-in input connector (16) with a plurality of pins, corresponding to the standard connectors (2a), a plug-in output connector (17) having a plurality of pines for connection to the multiprocessor (21) and said calibrating modules (29, 30 31) being arranged in parallel between these connectors.

14. A diagnostic apparatus as in claim 13, characterized in that the formatting interface (15) comprises a plurality of calibrating modules of the following type:

a module (29) for comparison of the status signal or the control signal with a calibrating threshold for delivering a logic signal as a function of that comparison, and/or a tracking amplifier module (31) able to provide a comparison for delivering a calibrated analog signal, and/or a mass control module (30) able to compare the input impedance at a calibration threshold, for delivering a logic signal as a function of the comparison.

15. A diagnostic apparatus as in claim 12, in which the memories for storage of the diagnostic programs are carried by an interchangeable card (25) comprising a bidirectional plug-in connector (27) for connection of said memories with the multiprocessor (21).

16. A diagnostic apparatus as in claim 13, characterized in that the multiprocessor (21) comprises at least six counters per processor (39, 40), associated in groups of different powers, for carrying out measurements of time on the calibrated logic signals and on combinations of different complexes of these signals.

17. A diagnostic apparatus as in claim 12, characterized in that the multiprocessor (21) comprises a plurality of multipath converters, of a number adapted for digitizing in parallel the calibrated analog signals.

18. An apparatus as in claim 12, characterized in that it comprises display means (5) and integrated manual selection means (6), the means for connecting the same with the multiprocessor being of the plug-in type.

19. An apparatus as in claim 18, characterized in that the display means comprises an alphanumeric screen (5) with at least four lines of twenty characters and the manual selection means comprising keys (6) for selecting and moving a cursor on the display screen (5).

20. An apparatus as in claim 12, characterized in that the connection with the man/machine interface comprises a retrievable connector in waiting.

21. An apparatus as in claim 20, characterized in that it comprises a standardized serial connection (46) connected to the multiprocessor (21) and having a retrievable connector (14) for connection with an external system for exchange with the multiprocessor.

22. An apparatus as in claim 16 comprising:

a parallelipipedic housing (1) open at two ends and provided internally with card receiving slots,

the formatting interface card (15) and the storage memory cards (25) being plugged in such a manner as to be removable from the slots,

a multiprocessor card (21),

a connection card (28) with the display means (5) and the manual selection means (6),

and two members (9,

     10) for closing the housing (1) at its open ends, one (9) being removable and carrying the inter-card connections and the other (10) carrying the input connectors (11-14) plugged into the formatting interface card (15).

23. An apparatus as in claim 22, characterized in that the housing (1) comprises a window (4) arranged on a front face, to the rear of which are provided the screen (5), the display means and sealed buttons (6) for manual selection, a protective cover (7) mounted on slides being associated with said front face to be able to be moved between two positions:

one position in which it hides and protects the display screen (5) and the manual selection buttons (6), and a position in which it reveals the latter.

24. An apparatus as in claim 23, characterized in that each wire harness (2) comprises resistors, differing from one harness to another, wired into said harness.

25. A formatting interface card (15) for use with an apparatus according to claim 12, characterized in that it comprises:

an plug-in input connector (16) having a plurality of pins,

a plug-in output connector (17) having a plurality of pins,

a plurality of calibrating modules (29, 30,

     31) arranged in parallel between the input and the output connectors.