JPH05171998A - Failure diagnosing system for vehicle - Google Patents

Abstract

PURPOSE:To prevent failure detection from being interfered with even when an ignition switch is turned off before storage of failure information, etc., is completed. CONSTITUTION:When a failure is detected, the detected place is stored in a failure history storage means 15, and the condition of an engine at that time is stored in a freeze frame memory 10. An error detection information calculating means 11 calculates error detection information to store the the information in an error detection information memory 12. When storage of failure history, freeze frame, and error detection information is completed, a failure detection completion judging means 16 judges that the failure detection is completed. Further, when an ignition switch is turned off before storage of various information is completed, it is judged that the failure detection is not completed. When the completion of failure detection is not judged, the failure history, freeze frame, and error detection information are erased when the ignition switch is again turned on.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle failure diagnosis system, and more particularly, to a vehicle that stores various kinds of failure information when a failure occurs and then estimates a failure cause and a failure location based on the failure information. The present invention relates to a failure diagnosis system.

[0002]

2. Description of the Related Art In order to improve an engine control function, an engine ignition timing control in an automobile or a motorcycle (hereinafter referred to as a vehicle), a fuel injection control using an injector, or the like is equipped with a microcomputer. It has come to be performed by an on-vehicle electronic control unit (ECU).

In a vehicle equipped with such an ECU, a failure of a portion related to a signal input to the ECU, E
The driver is automatically notified of the failure of the portion related to the signal output from the CU and the failure of the ECU itself, and various engine conditions such as engine speed, vehicle speed, cooling temperature, etc. at the time of the first failure occurrence ( Hereinafter, it may be referred to as a freeze frame) is stored in a battery-backed memory, and then the freeze frame is read at a maintenance shop or the like, and the cause of failure and the location of the failure are estimated based on this freeze frame. The system is being researched.

Further, in such a system, in order to detect so-called "garbled data" in which the freeze frame stored in the memory is destroyed by noise or the like, an arithmetic operation obtained from the freeze frame after the freeze frame is stored is detected. The sum and the parity are separately stored as error detection information, and then the arithmetic sum and the like obtained from the freeze frame and the arithmetic sum and the like stored as the error detection information are sequentially compared again, and if the two are different, " I try to judge that "has occurred."

By the way, in such a failure diagnosis system, while the failure is detected and various engine conditions are sequentially stored, that is, while the freeze frame is being created / stored, the ignition switch is turned off to cut off the power supply. If it is tampered with, the engine conditions that are not stored in the memory will disappear, so a halfway freeze frame will remain in the memory, and the error detection information obtained from the freeze frame and the error detection information stored in advance will be There was a problem that it was judged that the data became garbled due to inconsistency.

In order to solve such a problem, for example, when the ECU detects a power failure, an "end process" for continuing the creation and storage of the remaining freeze frames is executed, and the "end process" is executed. It will either stop after a complete freeze frame has been stored, or it will have a battery-backed buffer to store each engine condition and the memory will be removed from the buffer when the ignition switch is turned on again. A method for restarting the transfer of the remaining engine conditions to and continuing to create and store the freeze frame is conventionally known.

[0007]

However, since the engine condition stored as a freeze frame has a large amount of information, it takes a certain amount of time to store all the data in the memory, and the normal "end processing" is required. Can not deal with. Therefore, incomplete data will be stored as a freeze frame, and after the ignition switch is turned on again,
There is a problem that the error detection information obtained from the freeze frame and the error detection information stored in advance do not match, and it is determined that “garbled data” has occurred.

Further, in order to restart the storage after the ignition switch is turned on again, a large-capacity buffer memory for storing the engine condition is required, and there is a high possibility that the data is garbled. There was a problem that garbled data when the ignition switch was turned off could not be detected.

An object of the present invention is to solve all the above-mentioned problems of the prior art so that an error-free freeze frame can be obtained with a simple structure.

[0010]

In order to achieve the above object, the present invention relates to a failure information storage unit for storing failure information and a failure information storage unit in a vehicle failure diagnosis system having a freeze frame memory. Error detection information calculation means for calculating error detection information, error detection information storage means for storing the error detection information, and comparison means for comparing the newly calculated error detection information with the stored error detection information, When the storage of the failure information and the error detection information is completed, the failure detection end determination unit that determines that the failure detection is completed, the failure information storage unit, the error detection information storage unit, and the failure detection end determination unit are backed up by a battery. If the backup means and failure detection end judgment are not made, the failure information will be displayed when the ignition switch is turned on. And initializing means for erasing the error detection information, and when the comparing means determines that the respective error detection information match each other, the failure diagnosis is performed based on the stored failure information. The point is that it was done.

[0011]

According to the above configuration, if the ignition switch is turned off before the storage of the failure information and the error detection information is completed, it is determined that the failure detection is not completed, and the failure information at that time is determined. Since the error detection information and the error detection information are erased when the ignition switch is turned on again, the error detection information does not become inconsistent after the ignition switch is turned on again, and the ending process is simplified.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram of a vehicle failure diagnosis system according to an embodiment of the present invention.

The failure detecting means 14 detects an engine failure. The failure history storage means 15 includes the failure detection means 14
When an engine failure is detected by, the failure location is sequentially stored each time it is detected.

The freeze frame memory 10 stores engine conditions at the time of failure detection. Error detection information calculation means 1
Numeral 1 is, for example, arithmetic sum or parity is calculated as error detection information for checking the stored contents of the freeze frame memory 10. The error detection information storage means 12 stores the calculated error detection information. Comparison means 13
Compares the error detection information stored in the error detection information storage means 12 with the error detection information newly calculated by the error detection information calculation means 11.

The failure detection end determination means 16 determines whether or not the storage of each information in the failure history storage means 15, the freeze frame memory 10 and the error detection information storage means 12 is completed, and is completed. The failure detection end is determined and the determination result is stored. The ignition determination means 18 determines whether or not the ignition switch is on.

When the failure detection end determination means 16 determines that the failure detection is not completed, the initial setting means 17 erases the failure history, the freeze frame, and the error detection information when the ignition switch is turned on. .. The failure history storage means 15, freeze frame memory 10, error detection information storage means 12, and failure detection end determination means 16 are backed up by a battery.

In such a configuration, when some failure occurs during idling or running and this is detected by the failure detection means 14, the detected location is stored in the failure history storage means 15 and the engine at that time is detected. Number of revolutions,
Engine conditions such as vehicle speed and cooling temperature are stored in the freeze frame memory 10 as a freeze frame.

When all the data relating to the scheduled engine conditions are stored in the freeze frame memory 10, the error detection information calculation means 11 calculates the parity or arithmetic sum of the error detection information of the data. The calculated error detection information is stored in the error detection information memory 12.

When the storage of the failure history, the freeze frame, and the error detection information is completed as described above, the failure detection end determination means 16 determines that the failure detection is completed,
The determination result is stored. Further, when the ignition switch is turned off before the storage of any information is completed, the failure detection end determination means 16 determines that the failure detection is not completed, and stores the determination result.

After that, when carrying out a failure diagnosis in a maintenance shop or the like, the operator first detects the failure detection end determining means 16
If it is determined that the failure detection has ended, all of the engine conditions (freeze frame) stored in the freeze frame memory 10 and the failure history stored in the failure history storage means 15 are read out, and stored in these. Based on this, the cause and location of the failure are estimated.

Further, if the failure detection end determination is not made or the comparison means 13 determines that the error detection information does not match, the failure diagnosis based on the freeze frame is not performed. In addition, if the ignition detection unit 18 detects that the ignition switch is turned on again, especially when the failure detection end determination has not been made, the failure history, the freeze frame, and the error detection information are displayed by the initialization unit 17. Erased.

According to the present embodiment, if the ignition switch is turned off before the storage of the failure information and the error detection information is completed, the failure detection end determination is made, and the failure information and the error detection information at that time are Since the information is erased when the ignition switch is turned on again, the error detection information does not become inconsistent after the ignition switch is turned on again, and the ending process is simplified.

FIG. 2 is a block diagram of a vehicle failure diagnosis system according to another embodiment of the present invention, in which the same symbols as those used above represent the same or equivalent parts.

In the present embodiment, the failure detection end determination means 16
Error detection information storage means 19 for storing the error detection information relating to the determination result stored in, and true for determining “garbage” of the determination result based on the error detection information stored in the error detection information storage means 19. It is characterized in that it has a false decision means.

According to the present embodiment, error detection information is also provided in the failure detection end judgment indicating whether or not each data is stored in a complete form, and this garbled data is detected, so that it is more reliable. Highly accurate judgment is possible.

3 to 5 are flowcharts for explaining the operation of the embodiment described with reference to FIG.

When the ignition switch is in the ON state, the error detection information calculation means 11 is executed in step S101.
Calculates error detection information regarding the contents stored in the freeze frame memory 10. In steps S102 and S103, the comparison unit 13 compares the calculated error detection information with the error detection information stored in the error detection information storage unit 12.

If it is determined that they match each other, the process goes to step S104 to determine that the data is normal, and if they do not match, step S105.
Then, it is determined that a data abnormality has occurred due to garbled data.

In step S106, the failure detecting means 14
It is determined whether or not a failure has been detected by means of the failure detection. If a failure is detected, then in step S107 the failure history storage means 1
The failure history is stored in 5.

In step S108, it is determined whether the failure detection end flag FK, which will be described in detail later, is "1". If this is the first failure and the freeze frame is not stored, the flag FK is "0", and therefore the process proceeds to step S109. In step S109, each engine information is stored in the freeze frame memory 10 to create a freeze frame.

In step S110, the error detection information calculation means 11 calculates error detection information regarding the contents stored in the freeze frame memory 10. In step S111,
The calculated error detection information is the error detection information storage means 1
Stored in 2.

In this way, a freeze frame is created.
When the storage and the calculation / storage of the error detection information are completed, the failure detection end determination means 16 determines the end of the failure detection, and the failure detection end flag FK is set. Therefore, the freeze frame is not rewritten unless the flag FK is reset.

When the ignition switch is turned off, the ignition determination means 18 detects this and the end processing (see FIG. 4) is started. In step S201, the value of the flag FK is copied to the flag FK1. It is stored in the error detection information storage means 19.

After that, when the ignition switch is turned on again, the ignition judging means 18 detects it and starts the starting process (see FIG. 5). In step S301, the authenticity judging means 20 causes the flag FK and the flag FK1.
Are compared with each other, and if they match each other, step S303.
If no match is found, it is determined in step S302 that the data is abnormal.

In step S303, the flag FK is "1".
If it is determined that the flag FK is "0", that is, if the failure detection is not completed, the step S30 is performed.
In 4, the freeze frame memory 10 is cleared,
The error detection information storage means 12 is cleared in step S305, and the failure history storage means 15 is cleared in step S306.

[0036]

As described above, according to the present invention, when the ignition switch is turned off before the storage of the failure information such as the freeze frame and the failure history and the error detection information is completed, the failure detection is performed. Is judged not to have ended, and the failure information and error detection information at that time are erased when the ignition switch is turned on again.Therefore, each error detection information does not become inconsistent after the ignition switch is turned on again. Is also simplified.

[Brief description of drawings]

FIG. 1 is a block diagram of a failure diagnosis system that is an embodiment of the present invention.

FIG. 2 is a block diagram of a failure diagnosis system according to another embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of FIG.

FIG. 4 is a flowchart showing the operation of FIG.

FIG. 5 is a flowchart showing the operation of FIG.

[Explanation of symbols]

10 ... Freeze frame memory, 11 ... Error detection information calculation means, 12 ... Error detection information storage means, 13 ... Comparison means, 14 ... Failure detection means, 15 ... Failure history storage means, 1
6 ... Failure detection end judging means, 17 ... Initial setting means, 18
... ignition determination means, 19 ... error detection information storage means, 20 ... authenticity determination means

Claims (3)

[Claims] 1. Failure information storage means for storing failure information, error detection information calculation means for calculating error detection information relating to the stored failure information, and error detection information storage means for storing the error detection information. Comparing means for comparing the error detection information newly calculated with the stored error detection information, and when the storage of the failure information and the error detection information is completed,
Failure detection end determination means for determining that the failure detection has ended, backup means for backing up the failure information storage means, error detection information storage means, and failure detection end determination means with a battery, and failure detection end determination is not made And an initial setting unit that erases the failure information and the error detection information when the ignition switch is turned on, and when the comparison unit determines that the error detection information matches, the stored failure information. Vehicle failure diagnosis system that performs failure diagnosis based on 2. The vehicle failure diagnosis according to claim 1, wherein the failure information is at least one of a freeze frame indicating an engine condition when a first failure occurs and a failure history indicating a history of failure contents. system. 3. A second error detection information storage means for storing error detection information regarding storage contents of the failure detection end determination means, and a second backup means for backing up the second error detection information storage means by a battery. The vehicle failure diagnosis system according to claim 1 or 2, further comprising: a true / false determination unit that determines whether the failure detection end determination is true or false based on second error detection information.