JP3438270B2 - Data backup device and vehicle failure diagnosis device in electronic control system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data backup device in an electronic control system, for example, a backup device and a vehicle failure diagnostic device used in a failure diagnostic device for storing and retaining diagnostic data necessary for abnormality analysis of in-vehicle equipment.
It is about the table .

[0002]

2. Description of the Related Art This type of data backup device has been conventionally used in a failure diagnosis device or the like for storing and holding diagnostic data necessary for analyzing an abnormality of an on-vehicle device to carry out a failure diagnosis. That is, the diagnostic data of each part of the vehicle is sequentially updated at regular intervals in a backup memory that retains the contents even when the power is cut off, and the updated data is used to diagnose an abnormality (for example, , JP-A-62
No. 142849).

[0003]

However, in the above-mentioned failure diagnosing device, when the power is cut off during the data updating of the backup memory, the memory contents are mixed with the diagnostic data before the updating and the diagnostic data after the updating. It becomes a state. Then, when the power is turned on, the memory content in a state where the pre-updated data and the post-updated data are mixed is used for the failure diagnosis, which may deteriorate the accuracy of the failure diagnosis.

In short, in this type of electronic control system, if the control data before update and the control data after update are mixedly stored in the backup memory, the accuracy of the control data will be significantly reduced, There is a problem that the same data cannot be read from the backup memory and used.

The present invention has been made in view of the above problems, and an object of the present invention is to perform control before and after updating at the time of power-on even if the power is cut off during updating of control data. A data backup device and a vehicle failure diagnosis in an electronic control system that can surely perform control at power-on without using mixed data
To provide a device .

[0006]

In order to achieve the above object, a data backup device in an electronic control system according to claim 1 has a first, a second and a third storage area as shown in FIG. A backup memory M1 for storing and holding data even when the power is cut off, and a data updating means for sequentially updating the control data in the first storage area of the backup memory M1 in a routine started at a predetermined timing. M2, check data setting means M3 for setting check data in the third storage area of the backup memory M1 at the start of updating the control data by the data updating means M2, and resetting the check data at the end of the update, Prior to the start of updating the control data by the data updating means M2, the backup memory M1 of the backup memory M1 Data transfer means M4 for transferring control data stored in the storage area of the second storage area
And a data restoring means M5 for restoring the control data of the second storage area to the first storage area when the check data is set in the third storage area when the power is turned on. This is the summary. Well
The vehicle failure diagnosis device according to claim 2 is an in-vehicle device.
Fault diagnosis by storing and holding diagnostic data necessary for abnormality analysis of
A first, second, and third storage areas
And has the diagnostic data stored and retained even when the power is cut off.
Detects an abnormality in the backup memory and the in-vehicle device
The abnormality detecting means and the difference between the in-vehicle device by the abnormality detecting means.
If the constant is detected, the first of the backup memory
The diagnostic data stored and stored in the storage area of the
Data updating means for updating and the data updating means
Check data is backed up at the start of updating diagnostic data.
Set in the third storage area of the up memory and end the update
Check data that sometimes resets the check data
Difference between the setting means and the in-vehicle device by the abnormality detecting means
After normal detection, the diagnosis by the data updating means
Before starting the data update, the backup
Diagnostic data stored in the first storage area of the backup memory
Data transfer means for transferring data to the second storage area,
When the power is turned on, the check data is stored in the third storage area.
Data is set, the control data for the second storage area is set.
Data restoring means for restoring the data to the first storage area
The point is to have and. In addition, according to claim 3,
The vehicle failure diagnosis device is a vehicle failure diagnosis device according to claim 2.
In the disconnection device, the check data is
If the new means indicates whether or not the diagnostic data is being updated
Both are data for identifying the type of the diagnostic data.
That is the summary.

[0007]

The data updating means M2 sequentially updates the control data in the first storage area of the backup memory M1 in a routine started at a predetermined timing. The check data setting means M3 sets the check data in the third storage area of the backup memory M1 at the start of updating the control data by the data updating means M2, and resets the check data at the end of the update. Data transfer means M4
Transfers the control data stored in the first storage area of the backup memory M1 at the time of the previous update to the second storage area before the update of the control data by the data updating means M2 is started. If the check data is set in the third storage area when the power is turned on, the data restoration means M5
The control data in the second storage area is returned to the first storage area.

That is, if the power supply is cut off while the control data is being updated by the data updating means M2, the check data in the third storage area is held in the set state. At this time, the control data in the first storage area is a state in which the pre-update data and the post-update data are mixed, whereas the control data in the second storage area are all the control data in the previous routine. It is stored in a unified state. Then, when the power is turned on, it is determined whether or not the power is cut off while the control data is being updated, depending on the set state of the check data. In this case, if it is confirmed that the power is cut off, the control data in the second storage area is restored to the first storage area, so that the information including the control data before and after the update is mixed when the power is turned on. Control is performed without using. Furthermore, since the first storage area in which the control data before and after the update is mixed is rewritten to the control data without the mixture, the mixed control data is used when the control is restarted, and the control is adversely affected. There is no fear.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a data backup device in an electronic control system of the present invention is embodied in a vehicle failure diagnosis device will be described below with reference to the drawings.

FIG. 1 shows the electrical construction of the failure diagnosis apparatus in this embodiment. The control unit 1 includes a CPU (central processing unit) 4, a ROM (read only memory) 5, a RAM
(Random access memory) 6, input / output (I / O) circuit 7 and the like. CPU4, ROM5, RA
Power is supplied to the M6 and I / O circuit 7 from the battery 3 via the ignition switch 2. Power is directly supplied from the battery 3 to a part of the RAM 6 and serves as a backup RAM that retains stored contents even when the ignition switch 2 shuts off the power.

Sensor signals from sensors provided in various parts of the vehicle such as a throttle sensor 8, an air flow meter 9, a crank angle sensor 10 and a water temperature sensor 11 are input to the I / O circuit 7. The CPU 4 calculates the fuel injection amount according to each sensor signal using the control program in the ROM 5, and outputs an output signal according to this fuel injection amount to the fuel injection valve 12 via the I / O circuit 7. The engine operating condition (engine speed NE, intake air amount GN, etc.) is obtained from these sensor signals, and the same data is written in the backup RAM as diagnostic data when an abnormality is detected.

Further, in this failure diagnosis apparatus, the diagnostic checker 13 is connected to a connection port (not shown) of the I / O circuit 7.
Are connected. When the diagnostic checker 13 is connected to the I / O circuit 7, the diagnostic checker 13 requests the control unit 1 to output diagnostic data, etc.
Various diagnostic data (engine speed NE, intake air amount GN, failure code, etc.) written in the table are read out to perform abnormality diagnosis.

On the other hand, FIG. 2 shows the structure of the storage area of the backup RAM. The backup RAM has a word length of 16 bits, and as shown in FIG.
+ Α + α) has areas 201 to 213. Depending on the memory contents, this backup RAM forms an address n, which is a storage area for the backup RAM identification value, and (n + 1) to (n) which are temporary avoidance areas for various data.
The address is roughly divided into an address of + 2 + α and an address of (n + 3 + α) to (n + 5 + α + α) forming an access area for various data.

More specifically, in the area 201 corresponding to the address n, a backup RAM for identifying whether or not the data of the backup RAM is being updated.
The identification value is stored. That is, in the present embodiment, data (A5H) indicating update completion is set if it is in the initial state or outside the data update period of the backup RAM, and if it is within the period, predetermined check data different from the above (A5H) is set. It

Further, the abnormality determination flag A and the abnormality determination number A are stored in the areas 202 and 203 at the address (n + 1) which is the temporary avoidance area, respectively. Similarly, (n + 2 + 0) ~
In regions (204) to (206) of the address (n + 2 + α), diagnostic data such as engine speed NE, intake air amount GN, and failure code are stored. The data stored in these areas 202 to 206 becomes the data at the time of the previous update.

Further, it is a data access area (n +
Areas 207 to 210 of addresses 3 + α) and (n + 4 + α) store an abnormality determination flag and an abnormality determination count for determining whether the throttle sensor 8 and the water temperature sensor 11 are abnormal. Similarly, (n + 5 + α + 0) to (n +
The areas 211 to 213 at the address 5 + α + α) are the areas 2
It has the same number of bytes as 04 to 206, and the diagnostic data (engine speed NE, intake air amount GN, failure code, etc.) at each time is stored in each area.

In this embodiment, the CPU 4 constitutes a data updating means, a check data setting means, a data transferring means and a data restoring means. Moreover, the backup memory is configured by the backup RAM,
The area 201 of the backup RAM corresponds to the third storage area, the areas 202 to 206 correspond to the second storage area (temporary avoidance area), and the areas 207 to 213 correspond to the first storage area (data access area). ing.

Next, the operation of the failure diagnosis apparatus according to this embodiment will be described with reference to FIGS. The flowcharts of FIGS. 3 and 4 show the processing routines when the throttle sensor 8 and the water temperature sensor 11 are abnormal, and the flowcharts of FIGS. 5 and 6 show the subroutines of FIGS. 3 and 4. Further, the time chart of FIG. 7 shows the backup RAM during the predetermined steps of FIG.
The data rewriting operation of is shown. Further, the flowchart of FIG. 8 shows the data restoration processing routine at the time of power-on, and the flowchart of FIG. 9 shows the diagnostic checker 1
3 shows a data output routine to 3. Figure 3, Figure 4,
Each routine of FIG. 9 is performed at a predetermined cycle (in this embodiment, 8.2.
Every msec), the CPU 4 sequentially executes the routine, and the routine of FIG. 8 is executed by the CPU 4 only once when the power is turned on.

The processing of each routine will be briefly described. When an abnormality of the throttle sensor 8 or the water temperature sensor 11 is detected by the routines of FIGS.
Rewriting of AM data is performed. That is, the backup RAM stores data relating to the abnormality of the throttle sensor 8 or the water temperature sensor 11 according to the routines of FIGS. Then, the routine of FIG. 8 performs a process of restoring the backup RAM data when the power is shut off. Furthermore, the routine of FIG. 9 reads the data in the backup RAM to the diagnostic checker 13 and analyzes the abnormality.

The control contents of the above-mentioned routines will be described in detail below in order from FIG. Now, when the routine of FIG. 3 starts, the CPU 4 first executes the steps (hereinafter,
S) 301 and S302, the output signal of the throttle sensor 8 (hereinafter referred to as HA signal) is 0.1V to 4.9V.
It is determined whether or not it is within the range. If the HA signal is within this range, the CPU 4 determines that the throttle sensor 8 is functioning normally and proceeds to S312. CPU
4 clears the HA abnormality continuation counter in S312 and then ends this routine. Here, the HA abnormality continuation counter is adapted to be counted by the clock signal.

On the other hand, if the HA signal is out of the range of 0.1 V to 4.9 V, the CPU 4 proceeds to S303 to set the value of the HA abnormality continuation counter to a predetermined value (500 ms in this embodiment).
It is determined whether or not it is equal to or more than the value corresponding to. If the determination in S303 is affirmative, the CPU 4 determines that an abnormality has occurred in the throttle sensor 8 (HA abnormality) and S
Move to 304. The CPU 4 determines in S304 whether the HA abnormality is the first time. In this case, initially (HA
The abnormality determination first time) proceeds to S305, and the HA abnormality determination second time and thereafter ends the routine as it is.

In step S305, the CPU 4 calls the backup RAM rewriting start processing routine shown in FIG. Figure 5
In the subroutine of step S501, the CPU 4 copies the abnormality determination flag and the number of abnormality determinations to be rewritten, which are stored in the backup RAM areas 207 and 208 (see FIG. 2), to the temporary avoidance areas 202 and 203 in step S501. That is, in the case of HA abnormality, the HA abnormality determination flag and the HA abnormality determination number up to the previous time are stored as the abnormality determination flag A and the abnormality determination number A. Also, the CPU 4 executes S502
Then, the diagnostic data 0 (NE), 1 (GN), ... α (fault code) stored in the areas 211 to 213 at the time of the previous update are copied to the areas 204 to 206 for temporary avoidance,
Diagnostic data 0 '(NE), 1' (GN), ... α '
It is stored as (fault code). That is, S501,50
2, the data update process described later (S306 to S3 in FIG. 3).
As the preprocessing of 10), various data at the time of the previous update is transferred to the temporary avoidance area.

Thereafter, the CPU 4 writes the check data (00H) corresponding to the HA abnormality in the area 201 of the backup RAM in S503. That is, in the backup RAM identification value of this area 201, (A5H) is initially written as a value indicating the initial state or backup RAM update completion, but in S503, the check data (00H) different from this (A5H) is written. Is written. The check data is passed as a subroutine argument.

After that, the CPU 4 executes steps S306 to S3 of FIG.
Backup various data associated with this HA abnormality at 10 R
Write to the data access area of AM. Specifically, CP
U4 is the area 2 of the backup RAM in S306 of FIG.
The HA abnormality determination flag is set to "1" in 07, and S30
At 7, the number of HA abnormality determinations in the area 208 is counted up. The HA abnormality determination flag is held in the set state when the HA abnormality occurs, and the HA abnormality determination count is incremented by "1" for each process.

Further, the CPU 4 executes steps S308, 309, ...
・ At 310, diagnostic data 0 useful for analysis of the relevant HA abnormality,
1, ... α are obtained and sequentially stored in the backup RAM. That is, the CPU 4 obtains the engine speed NE, the intake air amount GN, etc. according to the operating state of the engine at that time, and the failure code (01H in the case of HA abnormality) determined by the type of abnormality, and backs it up. RAM area 2
The data are sequentially stored in 11 to 213.

Finally, the CPU 4 calls the backup RAM rewriting completion processing routine of FIG. 6 in S311, and terminates this routine. In the subroutine of FIG. 6, the CPU 4 writes a value (A5H) indicating update completion in the backup RAM identification value of the area 201 in S601.

As described above, when the HA abnormality is detected, the check data (00H) is set in the area 201 during the period from S305 (S503 in FIG. 5) to S311 (S601 in FIG. 6). Therefore, if the power is cut off during the same period, the backup RAM holds the check data (00H), and if the power is not cut off, the backup RAM holds the value (A5H) indicating the completion of the backup RAM update. become.

Next, an abnormal condition processing routine of the water temperature sensor 11 of FIG. 4 will be described. In FIG. 4, the CPU 4 determines in S401 and S402 whether or not the output signal of the water temperature sensor 11 (hereinafter referred to as TW signal) is in the range of 0.1V to 4.9V. Then, if the TW signal is within this range, the CPU 4 determines that the water temperature sensor 11 is functioning normally, and proceeds to S412. CPU4 is S412
After clearing the TW abnormality continuation counter in step 1, this routine ends.

On the other hand, if the TW signal is out of the range of 0.1 V to 4.9 V, the CPU 4 proceeds to S403 and sets the value of the TW abnormality continuation counter to a predetermined value (500 ms in this embodiment).
It is determined whether or not it is equal to or more than the value corresponding to. If the determination in S403 is affirmative, the CPU 4 determines that an abnormality has occurred in the water temperature sensor 11 (TW abnormality) and S40.
Go to 4. The CPU 4 determines in S404 whether the TW abnormality is the first one. In this case, initially (first TW abnormality determination), the process proceeds to S405, and TW abnormality determination 2 is performed.
The routine is ended after the first time.

In step S405, the CPU 4 calls the backup RAM rewriting start routine shown in FIG. In the subroutine of FIG. 5, in step S501, the CPU 4 copies the TW abnormality determination flag of the backup RAM areas 209 and 210 and the previous data of the number of times of TW abnormality determination to the temporary avoidance areas 202 and 203, and determines the abnormality determination flag A and the abnormality. The number of determinations is stored as A. Also, the CPU 4 executes S502
Then, the diagnostic data 0 (N
E), 1 (GN), ... α (fault code) are copied to the temporary avoidance areas 204 to 206, and diagnostic data 0 ′ (N
E), 1 '(GN), ... α' (fault code) are stored. Further, the CPU 4 determines the area 201 in S503.
The check data (01H) of the TW abnormality passed as a subroutine argument is written in the backup RAM identification value stored in.

Thereafter, the CPU 4 sets the TW abnormality determination flag of the area 209 to "1" in S406 of FIG.
In 407, the number of times of TW abnormality determination of the area 210 is counted up. Also, the CPU 4 uses S408, 409, ... 41.
When the value is 0, the engine speed NE, the intake air amount GN, the failure code (02H in the case of TW abnormality), etc. at the present time, which is useful for the abnormality analysis like the HA abnormality detection processing, are stored in the areas 211 to 211.
The diagnostic data of 213 are sequentially stored in 0, 1, ..., α.

Finally, the CPU 4 calls the above-mentioned subroutine of FIG. 6 in S411 to write the value (A5H) indicating the completion of updating the backup RAM in the area 201, and terminates this routine.

Here, S405 of FIG. 4 (S5 of FIG. 5)
The actual data rewriting operation of the backup RAM during the processing of (01) to S411 (S601 of FIG. 6) will be described with reference to the time chart of FIG. It should be noted that times t1 to t2 in FIG. 7 indicate a data update period.
In addition, in FIG. 7, HA is executed by the routine of FIG.
Abnormality is detected, backup RAM areas 211 to 2
It is assumed that the data for analysis at the time of HA abnormality is stored in 13 (NE = 1000 rpm, GN = 1.0 g / re
v, failure code = 01H).

In FIG. 7, before time t1, the area 209,
The TW abnormality determination flag of 210 and the number of times of TW abnormality determination are transferred to the areas 202 and 203.
13 pieces of diagnostic data have been transferred to the areas 204 to 206 (S501, 502). Also, at time t1, TW
Check data (01H) regarding abnormality is set in the area 201 (S503), and thereafter, various data are updated in this set state (S406 to S410). In FIG. 7, NE = 2000 rpm and GN = 1.5 are stored in the areas 211 to 213 as analysis data when the TW is abnormal.
g / rev and failure code = 02H are written.
At the time t2 when the data update is completed, the area 201
The identification value (A5H) is written in.

As can be seen from FIG. 7, when the power is cut off during the data update (time t1 to t2), the backup RAM identification value of the area 201 is the check data (01H in this case). It remains set. Therefore, by determining whether or not the same identification value is check data other than the value indicating the completion of backup update, it is possible to detect whether or not the diagnostic data is being updated.

Next, the data recovery processing routine of the backup RAM when the power is turned on will be described with reference to FIG. Now, when the power is turned on (ignition switch: on), the routine of FIG. 8 is started, and the CPU 4
First, in step S801, it is determined whether the identification value stored in the area 201 matches the value (A5H) indicating that the backup RAM has been updated. When they match, the CPU 4 determines that the update of the data in the backup RAM has been normally completed or that the backup RAM has not been written, and terminates this routine.

If they do not match, the CPU 4 determines that the power supply is cut off during the data updating of the backup RAM, and executes the processing of S802 to 805. That is, C
In S802 and 803, the PU 4 obtains the abnormality determination flag and the designated address of the backup RAM for restoring the number of abnormality determinations that have been temporarily avoided, based on the identification value of the area 201. Specifically, the CPU 4 sets the H
Based on the address (n + 3 + α) in which the A abnormality determination flag and the HA abnormality determination count are stored, the same (n + 3 +)
α) Offset (difference) between the address and the specified address of the return destination
To calculate. In the case of this embodiment, the check data (00H) and (01H) at the time of HA and TW abnormalities match the above offset, and the offset is either "0" or "1".

After that, in S803, the CPU 4 obtains the designated address by adding the offset in S802 to the address (n + 3 + α), and at that address, the abnormality determination flag A and the abnormality determination flag A stored in the temporary avoidance areas 202 and 203 are stored. Write the abnormality determination count A. In this case, if the HA is abnormal, the RAM designated address in S803 is (n + 3 + α).
+ 0 = (n + 3 + α), and if the TW is abnormal, S8
The RAM designated address of 03 is (n + 3 + α) + 1 =
(N + 4 + α).

Thereafter, in step S804, the CPU 4 stores the diagnostic data 0 '(NE), 1' (GN), ... α '(fault code) stored in the temporary avoidance areas 204 to 206 in the areas 211 to 211. It is copied to 213 and set as diagnostic data 0 (NE), 1 (GN), ... α (fault code) to be read. Further, in S805, the CPU 4 rewrites the check data in the area 201 with a value (A5H) indicating the completion of updating the backup RAM. That is, the check data is returned to the initial identification value. And CPU4
Ends this routine.

Now, the relationship between the power-off timing and the data held in the backup RAM will be described with reference to FIG. In FIG. 7, for example, time ta (S4
If the power is shut off immediately after (08), the diagnostic data 0 (NE) in the area 211 stores the data regarding the current TW abnormality, whereas the diagnostic data 1 (GN) in the areas 212 and 213, .. .alpha. (Fault code) holds the data about the previous HA abnormality. When the power is cut off at time tb (immediately after S406), the TW abnormality determination flag in the area 209 is "1".
In addition, an inconsistent situation occurs in which the number of times of TW abnormality determination in the area 210 becomes “0”. That is, when the power is cut off during the time t1 to t2 which is the data update period, a situation occurs in which the data before update and the data after update coexist in the data access area.

However, according to the restoration process of FIG. 8, whether or not the power is cut off during the data update is determined by the check data, and if the data update is in progress, the previous update data that is not mixed is stored in the data access area. Transferred. Therefore, there is no possibility that the CPU 4 accesses (reads) the mixed data before and after the update. Further, at this time, since all the mixed data in the data access area is rewritten by the data in the temporary avoidance area, the mixed data is not copied and confused when the routines of FIGS. 3 and 4 are restarted.

After the routine shown in FIG. 8 is executed, the routine shown in FIG.
Various data in the AM is output to the diagnostic checker 13.

In the routine of FIG. 9, the CPU 4 executes S
At 901, it is confirmed whether or not there is a data output request from the diag checker 13. If requested, CPU 4 outputs the abnormality determination flag of each address stored in the data access region of the backup RAM in S902, the abnormality determination count the die A grayed checker 13 via the I / O circuit 7. Until S903 is affirmatively determined, that is, until the abnormality determination flag and data of all addresses regarding the number of times are output, S902, 90
Repeat step 3. At this time, backup RAM
Of the HA abnormality stored in the areas 207 and 208 of the TW and the TW stored in the areas 209 and 210
The data relating to the abnormality are sequentially output. Then CP
U4 is an area 211 of the backup RAM in S904.
The diagnostic data stored in ～213 output to the die A grayed checker 13 via the I / O circuit 7, the routine ends.

As described above in detail, in the failure diagnosis apparatus of this embodiment, when an abnormality of the throttle sensor 8 or the water temperature sensor 11 is detected, first, the data access area (areas 207 ... 213) stores various data stored in the RAM in the temporary avoidance area (area 20).
2 to 206) (S501 and 502 in FIG. 5), and then various data in the data access area are sequentially updated (S306 to 310 in FIG. 3 and S406 in FIG. 4).
410). Further, during the data update period, predetermined check data (00H or 01H) is set in a predetermined area (area 201) of the backup RAM (S in FIG. 5).
503). Further, when the check data is set when the power is turned on, various data in the temporary avoidance area is restored to the data access area (S803, 804 in FIG. 8).

That is, when the power is cut off during the data update, the check data in the predetermined area is held in a set state, and the power cut can be easily identified by the check data when the power is turned on. And in this case,
By returning the data in the temporary avoidance area to the data access area, it is possible to perform the processing at power-on without using the mixed data before and after the update. That is, unlike the conventional case, there is no fear of degrading the accuracy of the abnormality diagnosis by using the data in the middle of updating, and the abnormality diagnosis can be always performed with high accuracy. Further, since all the mixed data before and after the update of the data access area can be rewritten to the data without mixing, it is possible to prevent confusion of control due to the use of the mixed data in the subsequent processing.

The present invention is not limited to the above embodiments, but can be embodied in the following modes. Although the failure diagnosis device of the above-described embodiment detects an abnormality regarding the throttle sensor 8 and the water temperature sensor 11, it may be configured to detect an abnormality of another sensor or device. In this case, a routine corresponding to the routines of FIGS. 3 and 4 may be newly set to provide an area corresponding to the storage area of the backup RAM.

In the above embodiment, the present invention is embodied as a vehicle failure diagnosis device, but it may be embodied as another electronic control system.

[0048]

As described above, according to the present invention, even if the power is cut off during the update of the control data, the control data before and after the update can be stored and held without being mixed, and the control data can be stored. By using, the excellent effect that the control when the power is turned on can be surely performed is exhibited.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electrical configuration of a failure diagnosis device according to an embodiment.

FIG. 2 is a configuration diagram showing a storage area of a backup RAM.

FIG. 3 is a flowchart showing a processing routine when a throttle sensor is abnormal.

FIG. 4 is a flowchart showing a processing routine when the water temperature sensor is abnormal.

FIG. 5 is a flowchart showing a backup RAM rewriting start processing routine which is a subroutine of FIGS. 3 and 4;

FIG. 6 is a flowchart showing a backup RAM rewriting completion processing routine, which is a subroutine of FIGS. 3 and 4;

FIG. 7 is a time chart showing a data rewriting operation of the backup RAM.

FIG. 8 is a flowchart showing a data recovery process of the backup RAM when the power is turned on.

FIG. 9 is a flowchart showing a routine for outputting data regarding abnormality analysis to a diagnostic checker.

FIG. 10 is a block diagram corresponding to a claim.

[Explanation of symbols]

1 ... Control unit, 4 ... Data updating means, check data setting means, data transfer means, CPU as data restoring means, 6 ... RAM provided with backup RAM.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G05B 9/02

Claims (3)

(57) [Claims] 1. A backup memory having first, second, and third storage areas, which stores and holds data even when power is cut off, and a backup memory which is stored in a routine started at a predetermined timing. Data updating means for sequentially updating the control data in the first storage area; check data is set in the third storage area of the backup memory at the start of updating the control data by the data updating means; And a check data setting unit for resetting the control data, and the control data stored in the first storage area of the backup memory at the time of the previous update before the update of the control data by the data updating unit is transferred to the second storage area. If the check data is set in the third storage area when the power is turned on and the data transfer means, And a data restoration means for restoring the control data of the serial second memory area in the first storage area, said check data, the by the data updating means
It indicates whether the control data is being updated, and
A data backup device in an electronic control system, which is data for identifying the type of data. 2. Diagnostic data necessary for abnormality analysis of in-vehicle equipment
Vehicle failure diagnosis device that stores and holds the
In addition, it has the first, second, and third storage areas, and even when the power is cut off,
A backup memory that stores and holds diagnostic data, an abnormality detecting unit that detects an abnormality of the vehicle-mounted device, and a case where the abnormality detection unit detects an abnormality of the vehicle-mounted device.
In the first storage area of the backup memory
Data update that sequentially updates the retained diagnostic data
At the start of updating the diagnostic data by the new means and the data updating means
Check data in the third section of the backup memory
Storage area and check data at the end of the update
Check data setting means for resetting, and after the abnormality detection of the in-vehicle device by the abnormality detection means.
Then, updating the diagnostic data by the data updating means
Before starting, the backup memory of
The diagnostic data stored in the first storage area is stored in the second storage area.
Data transfer means for transferring data to the storage area, and a check data in the third storage area when the power is turned on.
If the data is set, the diagnosis of the second storage area
Data recovery means for recovering data to the first storage area
A failure diagnosis device for a vehicle, comprising: a step. 3. The check data is the data update.
By means of indicating whether or not the diagnostic data is being updated by means
Mostly, it is data that identifies the type of diagnostic data.
The vehicle failure diagnosis device according to claim 2.