JP7099293B2 - Electronic control device - Google Patents

Description

The present disclosure relates to an electronic control device mounted on a vehicle.

For example, in Patent Document 1 below, as a function provided in an electronic control device mounted on a vehicle, when various diagnostic items (that is, diagnosis targets) are determined to be abnormal by failure diagnosis, information indicating an abnormality (that is, abnormality information) ) Is described. Further, for each diagnosis target, a function of storing a readiness flag when the failure diagnosis is completed is also described. The readiness flag referred to here corresponds to the diagnosis history information indicating that the failure diagnosis is completed, and is also called a readiness code. Completion of failure diagnosis means that the failure diagnosis determines whether it is normal or abnormal.

Such an electronic control device is configured so that the abnormality information and the readiness code stored in the memory can be read by a scan tool which is an external device.
Then, if the abnormality information is stored for any of the diagnosis targets, that is, if the abnormality information is read out, it can be determined that the diagnosis target is an abnormality. Further, if the abnormality information is not stored and the readiness code is stored for any of the diagnosis targets, it can be determined that the diagnosis target is normal.

Japanese Unexamined Patent Publication No. 2016-130094

As a result of the inventor's detailed examination of the electronic control device as described above, the following problems have been found.
For example, there are a target x and a target y as diagnosis targets, and the target x and the target y are "If the target x is not normal, even if a failure diagnosis (hereinafter, diagnosis Y) for the target y is performed, a correct diagnosis result is obtained. I can't get it. "

In this case, the electronic control device is configured to perform the diagnosis Y on condition that the target x is determined to be normal by the failure diagnosis (hereinafter, diagnosis X) for the target x.
Then, at a certain timing, it is assumed that the subject x is determined to be normal by the diagnosis X, and then the diagnosis Y is performed and the subject y is determined to be normal.

At this point, since the diagnosis X and the diagnosis Y have been completed at least once, both the readiness code for the target x and the readiness code for the target y are stored in the memory of the electronic control device. become.

After that, it is assumed that an abnormality occurs in the target x and the target x is determined to be abnormal by the diagnosis X. At this time, the abnormality information about the target x is stored in the memory of the electronic control device. On the other hand, since the target x is determined to be abnormal, the diagnosis Y is not performed.

At this point, the memory of the electronic control device stores the readiness code and the abnormality information for the target x, and stores only the readiness code among the readiness code and the abnormality information for the target y. become. That is, as the stored contents of the memory, the target x is the stored contents determined to have an abnormality, and the target y is the stored contents determined to be normal.

Therefore, for example, in the process of vehicle inspection and maintenance or vehicle inspection, if the abnormality information and the readiness code are read by the scan tool from the electronic control device in such a state, it is determined that the target x has an abnormality. , The target y is judged to be normal. That is, the diagnosis Y has not been performed in the latest state due to the occurrence of the abnormality in the target x, and the target y is judged to be normal even if there is an abnormality.

Therefore, for example, it is considered that the target x is repaired because the abnormality information is stored. However, since the target y is judged to be normal, after the target x is repaired, when it is considered that the diagnosis X of the diagnosis X and the diagnosis Y is completed in the electronic control device, the reading by the scan tool is performed again. , There is a high possibility that it will be confirmed that it is normal only for the target x. In this case, even if there is an abnormality in the target y, the abnormality in the target y is overlooked. Therefore, in the case of vehicle inspection and maintenance, it is easy to cause insufficient confirmation after the repair of the target x. Further, in the case of vehicle inspection, for the target y, the latest failure diagnosis after the target x is repaired has not been carried out, and the vehicle that should be rejected is passed. there is a possibility.

Therefore, one aspect of the present disclosure is that when the predetermined diagnosis target becomes abnormal with respect to another diagnosis target for which the failure diagnosis is performed on the condition that the predetermined diagnosis target is determined to be normal. Provided is an electronic control device capable of preventing the diagnosis history information before the occurrence of the abnormality from remaining in the storage unit.

The electronic control device according to one aspect of the present disclosure is an electronic control device mounted on a vehicle, and includes a storage unit (11), a first diagnostic unit (S110 to S230, S110 to S240), and a second diagnostic unit (S110 to S240). S310 to S390, S310 to S370) and an erasing unit (S380, S390, S240).

The first diagnosis unit carries out a failure diagnosis for a predetermined diagnosis target, and when the failure diagnosis is completed, the diagnosis history information for the predetermined diagnosis target is stored in the storage unit, and the predetermined diagnosis target is determined by the failure diagnosis. If it is determined to be abnormal, the abnormality information about the predetermined diagnosis target is stored in the storage unit.

The second diagnosis unit carries out a failure diagnosis for another diagnosis target, which is a diagnosis target different from the predetermined diagnosis target, on condition that the predetermined diagnosis target is determined to be normal by the first diagnosis unit. When the failure diagnosis is completed, the diagnosis history information about the other diagnosis target is stored in the storage unit, and when the failure diagnosis determines that the other diagnosis target is abnormal, the abnormality information about the other diagnosis target is stored in the storage unit. Remember.

Then, when the first diagnosis unit determines that the predetermined diagnosis target is abnormal, the erasing unit erases the diagnosis history information about another diagnosis target from the storage unit.
According to the electronic control device provided with such an erasing unit, the predetermined diagnosis target becomes abnormal with respect to another diagnosis target for which the failure diagnosis is performed on the condition that the predetermined diagnosis target is determined to be normal. In that case, it is possible to prevent the diagnosis history information before the occurrence of the abnormality from remaining in the storage unit. Therefore, when the abnormality information about the predetermined diagnosis target is stored in the storage unit and the predetermined diagnosis target is repaired, the diagnosis target for which the failure diagnosis has not been completed, that is, the diagnosis target for which rediagnosis must be performed is performed. Be clear. Therefore, when the information stored in the storage unit of the electronic control device is read out and used for inspection and maintenance of the vehicle, the above-mentioned insufficient confirmation after repair can be suppressed, and when it is used for vehicle inspection, it can be suppressed. , It is possible to suppress the possibility of passing a vehicle that should be rejected.

It is a block diagram which shows the structure of the electronic control apparatus of 1st Embodiment. It is a flowchart which shows the 1st diagnostic process performed by the microcomputer of 1st Embodiment. It is a flowchart which shows the 2nd diagnostic process performed by the microcomputer of 1st Embodiment. It is a flowchart which shows the process to perform when a tool is used for vehicle inspection maintenance. It is a flowchart which shows the process which performs processing when a tool is used for vehicle inspection. It is a flowchart which shows the 2nd diagnostic process performed by the comparative example and the microcomputer of 2nd Embodiment. It is explanatory drawing explaining the operation by the electronic control device of the comparative example. It is explanatory drawing explaining the operation by the electronic control apparatus of 1st Embodiment. It is a flowchart which shows the 1st diagnostic process performed by the microcomputer of 2nd Embodiment. It is explanatory drawing explaining the 3rd Embodiment.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[1. First Embodiment]
[1-1. Constitution]
The electronic control unit (hereinafter referred to as ECU) 1 of the first embodiment shown in FIG. 1 is an ECU mounted on a vehicle and controlling, for example, a power source of the vehicle. ECU is an abbreviation for "Electronic Control Unit". In the present embodiment, the power source as a control target is an internal combustion engine (hereinafter referred to as an engine), but a motor may also be used.

The ECU 1 includes a microcomputer (hereinafter referred to as a microcomputer) 3 that performs each process including a process for controlling a controlled object.
The microcomputer 3 includes a CPU 5 that executes a program, a ROM 7 that stores a program executed by the CPU 5 and data referred to when the program is executed, a RAM 9 for temporarily storing the data, and another memory 11. And. Each operation of the microcomputer 3 described later is realized by executing a program by the CPU 5.

The memory 11 is a memory capable of holding data even when the operation of the microcomputer 3 is stopped, in other words, the operation of the ECU 1 is stopped. The memory 11 may be, for example, a standby RAM to which power for holding data is constantly supplied, or may be a rewritable non-volatile memory such as an EEPROM or a flash memory.

Signals from one or more sensors 13 that detect information for controlling the engine are input to the ECU 1, and signals from the one or more sensors 13 are input to the microcomputer 3. Although only one sensor 13 is shown in FIG. 1, for example, a water temperature sensor that detects the cooling water temperature of the engine, an air-fuel ratio sensor that detects the air-fuel ratio, and an intake pressure that detects the intake air pressure of the engine. There are sensors, etc.

The microcomputer 3 performs a control calculation based on information from one or more sensors 13, and controls the drive of one or more electric loads 15 related to engine control based on the calculation result. Although only one electric load 15 is shown in FIG. 1, for example, there are an injector for injecting fuel into the engine, an ignition device for igniting the cylinder of the engine, and the like.

Further, the ECU 1 is connected to a communication bus 17 arranged in the vehicle. The communication bus 17 is also connected to one or more other ECUs 18 mounted on the vehicle.
Further, a scan tool (hereinafter, tool) 23 as a vehicle diagnostic device can be attached to and detached from the communication bus 17 via the connector 21. The tool 23 may be, for example, a handy type device including a microcomputer and a display (that is, a display device), or may be a personal computer. Then, the microcomputer 3 of the ECU 1 can communicate with the tool 23 and other ECUs 18 via the communication bus 17.

Further, the microcomputer 3 is configured to perform failure diagnosis for a plurality of diagnosis targets (that is, diagnosis items). Then, when the failure diagnosis is completed, the microcomputer 3 stores in the memory 11 a readiness code corresponding to the diagnosis history information indicating that the failure diagnosis is completed. Further, the microcomputer 3 stores an abnormality code (that is, DTC) as abnormality information in the memory 11 for the diagnosis target determined to be abnormal by the failure diagnosis. DTC is an abbreviation for "Diagnostic Trouble Code". Further, the microcomputer 3 also has a function of reading the DTC and readiness code for each diagnosis target stored in the memory 11 and transmitting them to the tool 23 in response to the read request from the tool 23.

One of the plurality of diagnostic targets is a water temperature sensor. The water temperature sensor outputs, for example, a signal of a voltage corresponding to the cooling water temperature of the engine.
Further, as another one of the plurality of diagnostic targets, there is a thermostat. The thermostat is provided, for example, in the cooling water path between the engine and the radiator, and is configured to open the valve when the cooling water temperature around the thermostat exceeds a predetermined set temperature.

[1-2. Processing performed by the ECU microcomputer]
Next, among the plurality of failure diagnoses performed by the microcomputer 3, each failure diagnosis for the two diagnosis targets will be described with reference to the flowcharts of FIGS. 2 and 3.

The microcomputer 3 performs a failure diagnosis (hereinafter referred to as diagnosis A) for the water temperature sensor by performing the first diagnosis process of FIG. In FIG. 2, the processes of S120 to S220 are the processes of diagnosis A. Further, the microcomputer 3 performs a failure diagnosis (hereinafter referred to as diagnosis B) for the thermostat by performing the second diagnosis process of FIG. In FIG. 3, the processes of S330 to S360 are the processes of diagnosis B.

The first diagnostic process and the second diagnostic process are executed, for example, at predetermined time intervals having different lengths and at different timings. For example, the first diagnostic process is performed every 1 second and the second diagnostic process is performed every 10 seconds. In the following description, the diagnosis A may refer to the process of the diagnosis A, and similarly, the diagnosis B may refer to the process of the diagnosis B.

[1-2-1. First diagnostic process]
As shown in FIG. 2, when the first diagnosis process is started, the microcomputer 3 determines in S110 whether or not a predetermined common condition for carrying out the failure diagnosis is satisfied, and the common condition is satisfied. If it is determined that the case is not present, the first diagnostic process is terminated.

Further, when the microcomputer 3 determines in S110 that the common condition is satisfied, the microcomputer 3 proceeds to S120 and acquires the sensor voltage (that is, the output voltage) from the water temperature sensor as the diagnosis target. Then, in S130, the microcomputer 3 determines whether the sensor voltage is equal to or higher than the predetermined upper limit value, is equal to or lower than the predetermined lower limit value, or is within the range from the upper limit value to the lower limit value (that is, the normal range). , Is determined.

When the microcomputer 3 determines in S130 that the sensor voltage is equal to or higher than the upper limit value, S
At 140, the short state counter is counted up (that is, incremented), and at S150, it is determined whether or not the value of the short state counter is equal to or greater than a predetermined value.

When the microcomputer 3 determines in S150 that the value of the short state counter is not equal to or higher than the predetermined value, the microcomputer 3 ends the first diagnostic process, but determines that the value of the short state counter is equal to or higher than the predetermined value. In that case, the process proceeds to S160.

In S160, the microcomputer 3 determines that the signal line of the water temperature sensor, that is, the signal line for inputting the sensor voltage from the water temperature sensor to the ECU 1, has a short-circuit abnormality, and the water temperature sensor has a short-circuit abnormality. The DTC indicating that the sensor is stored is stored in the memory 11. The short circuit abnormality referred to here is a short circuit to a line having a voltage higher than the normal sensor voltage (for example, battery voltage). As another example, in S160, the microcomputer 3 may set, for example, a short error flag in the RAM 9 instead of storing the DTC in the memory 11. In this case, the microcomputer 3 refers to the short abnormality flag in the DTC storage process executed at a timing different from the first diagnostic process, and if this flag is set, the water temperature sensor has a short error. The DTC indicating that the above is generated may be stored in the memory 11.

Further, when the microcomputer 3 determines in S130 that the sensor voltage is equal to or less than the lower limit value, the open state counter is counted up in S170, and the value of the open state counter is set to a predetermined value in S180. It is determined whether or not the above is the case.

When the microcomputer 3 determines in S180 that the value of the open state counter is not equal to or higher than the predetermined value, the microcomputer 3 terminates the first diagnostic process, but determines that the value of the open state counter is equal to or higher than the predetermined value. In that case, the process proceeds to S190.

In S190, the microcomputer 3 determines that an open abnormality (that is, a disconnection abnormality) has occurred in the signal line of the water temperature sensor, and stores a DTC indicating that an open abnormality has occurred in the water temperature sensor in the memory 11. .. As another example, in S190, the microcomputer 3 may set, for example, an open abnormality flag in the RAM 9 instead of storing the DTC in the memory 11. In this case, the microcomputer 3 refers to the open abnormality flag in the DTC storage process executed at a timing different from the first diagnostic process, and if this flag is set, the water temperature sensor has an open abnormality. The DTC indicating that the above is generated may be stored in the memory 11.

Further, when the microcomputer 3 determines in S130 that the sensor voltage is within the normal range from the upper limit value to the lower limit value, the normal state counter is counted up in S200 and normal in S210. Determines whether the value of the status counter is equal to or greater than a predetermined value.

When the microcomputer 3 determines in S210 that the value of the normal status counter is not equal to or higher than the predetermined value, the microcomputer 3 terminates the first diagnostic process, but determines that the value of the normal status counter is equal to or higher than the predetermined value. In that case, the process proceeds to S220.

In S220, the microcomputer 3 determines that the water temperature sensor is normal (that is, no abnormality), and sets, for example, a normal flag in the RAM 9 indicating that the water temperature sensor is normal. When this normal flag is set, the DTC stored in the memory 11 for the water temperature sensor is erased. Further, in the case of the configuration in which the short abnormality flag and the open abnormality flag in the RAM 9 are set in each of the above S160 and S190, in the S220, the short abnormality flag and the open abnormality flag in the RAM 9 are reset (that is, cleared). It's okay.

Then, when any of the above processes S160, S190, and S220 is performed, that is, when the diagnosis A is completed, the microcomputer 3 proceeds to S230 and sets the readiness code of the diagnosis A. That is, the readiness code indicating that the diagnosis A is completed is stored in the memory 11. After that, the microcomputer 3 ends the first diagnostic process.

As another example, a DTC indicating that a short-circuit abnormality has occurred in the water temperature sensor and a DTC indicating that an open abnormality has occurred in the water temperature sensor are not separately provided, for example, S160 and S190. The DTC indicating an abnormality of the water temperature sensor may be stored in the memory 11.

[1-2-2. Second diagnostic process]
As shown in FIG. 3, when the microcomputer 3 starts the second diagnostic process, is the water temperature sensor normal in S310 based on the determination result (that is, the failure diagnosis result) of the water temperature sensor by the first diagnostic process? Judge whether or not. Specifically, it is determined whether or not the failure diagnosis result of the water temperature sensor by the first diagnostic process is a result indicating normality.

When the microcomputer 3 determines in S310 that the water temperature sensor is normal, the microcomputer 3 proceeds to S320, determines whether or not the above-mentioned common conditions are satisfied, and when it is determined that the common conditions are not satisfied. Ends the second diagnostic process.

Further, when the microcomputer 3 determines in S320 that the common condition is satisfied, the microcomputer 3 proceeds to S330 and determines whether or not a predetermined time has elapsed after starting the engine. If the microcomputer 3 determines in S330 that the predetermined time has not elapsed, the microcomputer 3 ends the second diagnostic process, but if it determines that the predetermined time has elapsed, the microcomputer 3 proceeds to S340.

In S340, the microcomputer 3 calculates the cooling water temperature based on the sensor voltage from the water temperature sensor, and determines whether or not the calculated cooling water temperature is equal to or higher than a predetermined value. If it is determined that the cooling water temperature is not higher than the predetermined value, the process proceeds to S360, and it is determined that the thermostat is not functioning normally (that is, abnormal), and the DTC indicating that the thermostat is abnormal is determined. Store in memory 11. As another example, in S360, the microcomputer 3 may set the thermostat abnormality flag in the RAM 9, for example, instead of storing the DTC in the memory 11. In this case, the microcomputer 3 refers to the thermostat abnormality flag in the DTC storage process executed at a timing different from the second diagnostic process, and if this flag is set, the thermostat is abnormal. The DTC indicating that may be stored in the memory 11.

Further, when the microcomputer 3 determines in the above S340 that the cooling water temperature is equal to or higher than a predetermined value, the microcomputer 3 proceeds to S350 and determines that the thermostat is functioning normally (that is, normal), for example. Set the normal flag in RAM 9 indicating that the thermostat is normal. When this normal flag is set, the DTC stored in the memory 11 for the thermostat is erased. Further, in the case of the configuration in which the thermostat abnormality flag in the RAM 9 is set in the above S360, the thermostat abnormality flag may be reset in the S350.

Then, when any of the above processes S350 and S360 is performed, that is, when the diagnosis B is completed, the microcomputer 3 proceeds to S370 and sets the readiness code of the diagnosis B. That is, the readiness code indicating that the diagnosis B is completed is stored in the memory 11. After that, the microcomputer 3 ends the second diagnostic process.

If the water temperature sensor is not determined to be normal in the above S310, the microcomputer 3 proceeds to S380, and based on the determination result (that is, the failure diagnosis result) of the water temperature sensor by the first diagnostic process. Determine if the water temperature sensor is abnormal. Specifically, it is determined whether or not the failure diagnosis result of the water temperature sensor by the first diagnostic process is a result indicating a short-circuit abnormality or an open abnormality.

When the water temperature sensor is determined to be abnormal in S380, that is, when the water temperature sensor is determined to be abnormal by the first diagnostic process, the microcomputer 3 outputs the readiness code of the diagnosis B from the memory 11 in S390. It is cleared (that is, erased), and then the second diagnostic process is terminated. Further, if the water temperature sensor does not determine that the water temperature sensor is abnormal in S380, the microcomputer 3 ends the second diagnosis process as it is.

[1-3. What the tool does]
Next, as an example of the processing performed by the tool 23, the processing when the tool 23 is used for vehicle inspection and maintenance and the processing when the tool 23 is used for vehicle inspection (that is, vehicle inspection) are described. This will be described with reference to the flowcharts of FIGS. 4 and 5.

[1-3-1. What to do when the tool is used for vehicle inspection and maintenance]
When the tool 23 is used for vehicle inspection and maintenance at, for example, a car dealer or a vehicle maintenance shop, the tool 23 performs the process of FIG.

The tool 23 is connected by the operator to the communication bus 17 of the vehicle via the connector 21.
Then, as shown in FIG. 4, the tool 23 reads the readiness code and the DTC stored in the memory 11 from the ECU 1 by communicating with the ECU 1 in S410.

In the next S420, the tool 23 identifies and records an incomplete failure diagnosis in the ECU 1 among a plurality of predetermined failure diagnoses based on the readiness code read from the ECU 1. The plurality of predetermined failure diagnoses are a plurality of failure diagnoses that are to be performed by the ECU 1. Specifically, the tool 23 identifies the failure diagnosis corresponding to the readiness code not read from the ECU 1 as the incomplete failure diagnosis among the plurality of predetermined failure diagnoses.

The tool 23 determines whether or not the DTC has been read from the ECU 1 in the next S430, and if the DTC has not been read, proceeds to S440.
In S440, the tool 23 determines whether or not all failure diagnoses have been completed in ECU 1 by referring to the recording result in S420.

Then, when the tool 23 determines in S440 that all the failure diagnoses have been completed, that is, when the DTC is not read from the ECU 1 and all the failure diagnoses have been completed in the ECU 1. Proceed to S450.

The tool 23 determines that there is no failure in S450. Then, for example, a display is displayed to inform the operator that there is no failure, in other words, that repair is not necessary.
Further, if the tool 23 makes a negative determination in S440, that is, if it is determined that the DTC has not been read from the ECU 1 but at least one failure diagnosis has not been completed in the ECU 1, the tool 23 proceeds to S460. ..

In S460, the tool 23 displays the information indicating the incomplete failure diagnosis recorded in S420 on the display, and causes the operator to perform the vehicle driving work so that the incomplete failure diagnosis is performed by the ECU 1. A message for (ie, prompting) is displayed on the display. It should be noted that the display of the information indicating the incomplete failure diagnosis on the display may be performed by, for example, S420.

Therefore, in this case, the operator removes the tool 23 from the communication bus 17 and drives the vehicle. Driving a vehicle by an operator is a so-called test run. Then, the operator drives the vehicle until it is considered that the failure diagnosis that has not been completed by the ECU 1 is completed, and then the tool 23 is connected to the communication bus 17 again, and the tool 23 performs the process of FIG. Let me. The operator can know, for example, from a vehicle maintenance manual or the like, how much or how the vehicle should be driven so that each failure diagnosis is performed by the ECU 1.

If the tool 23 determines in S430 that the DTC has been read from the ECU 1, the tool 23 proceeds to S470. In the following, the DTC read from the ECU 1 to the tool 23 is also referred to as a detection DTC.

In S470, the tool 23 displays the content of the detected DTC or the abnormality indicated by the detected DTC and the information indicating the incomplete failure diagnosis recorded in S420 on the display. Further, in S470, the tool 23 displays a message on the display for causing the operator to perform (that is, prompting) the following first and second operations.

The first work is the repair work of the abnormality indicated by the detection DTC. The second work is a vehicle driving work after performing the above repair work, and is a vehicle driving work for enabling the ECU 1 to perform the failure diagnosis corresponding to the repaired portion and the incomplete failure diagnosis.

Therefore, in this case, the operator removes the tool 23 from the communication bus 17 and repairs the abnormality. Then, after the repair is carried out, the operator drives the vehicle until it is considered that the failure diagnosis corresponding to the detected DTC and the incomplete failure diagnosis are completed by the ECU 1, and then the tool 23 is connected to the communication bus 17 again. Then, the tool 23 is made to perform the process of FIG.

[1-3-2. What to do if the tool is used for vehicle inspection]
The failure diagnosis function provided in the ECU 1 is called a self-diagnosis function and is also called an OBD. OBD is an abbreviation for "On-Board Diagnostics". In recent years, the implementation of vehicle inspections utilizing OBD (hereinafter referred to as OBD vehicle inspections) has been considered. In the OBD vehicle inspection, the DTC for one or more specific diagnosis targets among the plurality of DTCs is defined as the specific DTC. When any specific DTC is read out from the vehicle side at the time of performing the OBD vehicle inspection, it means that the diagnosis target corresponding to the specific DTC is determined to be abnormal by the OBD. It is rejected. Further, if the specific DTC is not read from the vehicle side and all the readiness codes corresponding to all the specific DTCs are read, the diagnosis target corresponding to all the specific DTCs is determined to be normal by OBD. Since it means that, it is considered to be passed.

Therefore, when the tool 23 is used for OBD vehicle inspection, the tool 23 performs the process of FIG.
Of the plurality of DTCs that may be stored in the ECU 1, at least each DTC of diagnosis A and diagnosis B is assumed to be a specific DTC.

When the OBD vehicle inspection is carried out, the tool 23 is connected by the operator to the communication bus 17 of the vehicle via the connector 21.
Then, as shown in FIG. 5, the tool 23 reads the readiness code and the specific DTC stored in the memory 11 from the ECU 1 by communicating with the ECU 1 in S510.

In the next S520, the tool 23 determines whether or not at least one specific DTC has been read from the ECU 1 in the above S510, and if the specific DTC is not read, that is, the specific DTC is stored in the ECU 1. If not, proceed to S530.

In S530, the tool 23 determines whether or not the readiness codes corresponding to all the specific DTCs have been read from the ECU 1 in S510, that is, whether or not the readiness codes corresponding to all the specific DTCs are set in the ECU 1. To judge.

Then, when the tool 23 affirmatively determines in S530 that the readiness codes corresponding to all the specific DTCs have been read from the ECU 1, the tool 23 determines in the next S540 that the vehicle has passed. For example, a message indicating acceptance is displayed on the display.

Further, when the tool 23 determines in the S520 that the specific DTC has been read from the ECU 1, or in the negative determination in the S530, that is, the readiness code corresponding to at least one specific DTC is from the ECU 1. If it is not read, the process proceeds to S550.

Then, the tool 23 determines that the vehicle has failed in S550, and displays, for example, a message indicating the failure on the display.
Further, when there is a specific DTC read from the ECU 1 in S510, the tool 23 displays the read specific DTC or the content of the abnormality indicated by the specific DTC on the display in S550. Further, if there is a readiness code not read from the ECU 1 in S510 among all the readiness codes corresponding to the specific DTC, the tool 23 performs a failure diagnosis corresponding to the readless readness code. Identify as an incomplete failure diagnosis. Then, the information indicating the identified incomplete failure diagnosis is displayed on the display in S550.

Therefore, when the vehicle fails, the operator can know the abnormality content and the incomplete failure diagnosis from the content displayed on the display of the tool 23.
[1-4] Comparative Example Here, in order to make it easy to understand the effect of the ECU 1 of the embodiment, the ECU of the comparative example will be described. Since the basic configuration of the ECU of the comparative example is the same as that of the ECU 1 of the embodiment, the differences will be described below. In the description of the ECU of the comparative example, the same reference numerals as those of the ECU 1 of the embodiment indicate the same configuration, and the preceding description will be referred to.

The ECU of the comparative example is different from the ECU 1 of the embodiment in that the microcomputer 3 performs the second diagnostic process of FIG. 6 instead of the second diagnostic process of FIG. Then, in the second diagnostic process of FIG. 6, S380 and S390 are deleted as compared with the second diagnostic process of FIG. 3, and if the water temperature sensor is not determined to be normal in S310, it is the same as it is. The second diagnostic process is terminated.

Next, the operation of the comparative example by the ECU will be described with reference to FIG. 7.
In FIG. 7, of the high or low of the rectangular wave described in the “Driving Cycle” stage (that is, the first stage), the high period is the period during which power is supplied to the ECU and the ECU operates. Then, one cycle from the time when the square wave becomes high to the next time when the rectangular wave becomes high is one driving cycle (hereinafter referred to as DC). The DC referred to here is a period from when the power source for power for operating the power of the vehicle is turned on to when the power is turned on next. The ECU operates, for example, while the power source for power of the vehicle is on. The power source for power may be, for example, a power source supplied by turning on the ignition switch, but in the case of an electric vehicle or a hybrid vehicle, it may be a power source supplied by turning on the power switch. Further, in FIG. 7, "undetermined" means that neither normal nor abnormal is determined by the failure diagnosis in the ECU, and in particular, in the stage of the readiness code, "undetermined" means that the readiness code is It means that it is not set, that is, it is not remembered. Further, in the stage of the readiness code, "determination completed" means that the readiness code is set, that is, stored. The same applies to FIGS. 8 and 10 described later.

As shown in FIG. 7, it is assumed that the water temperature sensor is first determined to be normal by the diagnosis A at the 1st DC. Then, the readiness code of diagnosis A is set.
Further, if the water temperature sensor is determined to be normal by the diagnosis A at the 1st DC, the execution condition of the diagnosis B is satisfied, and then the diagnosis B is performed. Then, it is assumed that the thermostat is determined to be normal by the diagnosis B. Then, the readiness code of diagnosis B is set.

The readiness code stored in the memory 11 is held, for example, until the tool 23 issues an initialization command such as service clear to the ECU.
Next, at the 2nd DC, it is assumed that the water temperature sensor is determined to be abnormal by the diagnosis A. Specifically, it is assumed that a short circuit abnormality or an open abnormality has occurred in the signal line of the water temperature sensor. Then, the DTC related to the water temperature sensor, that is, the DTC indicating that a short-circuit abnormality or an open abnormality has occurred is stored in the memory 11. The readiness code of diagnosis A is already set at the 1st DC.

Then, at the 2nd DC, the diagnosis B is not carried out because the execution condition of the diagnosis B is not satisfied because the water temperature sensor is determined to be abnormal in the diagnosis A. That is, at the 2nd DC, the diagnosis B is undetermined. However, since the readiness code of the diagnosis B is set at the 1st DC, it indicates that the diagnosis B is completed.

Here, it is assumed that the DTC and the readiness code are read by the tool 23 from the ECU of the comparative example in such a second DC state, for example, for inspection and maintenance of the vehicle.
In this case, at least the DTC by the diagnosis A, that is, the DTC related to the water temperature sensor, the readiness code of the diagnosis A, and the readiness code of the diagnosis B are read from the ECU to the tool 23.

Therefore, the tool 23 determines "YES" in S430 of FIG. 4, and the process of S470 prompts the worker to carry out the above-mentioned first work and second work.
In this case, the first work is the repair work of the water temperature sensor. The second work is a vehicle driving work for enabling the ECU to perform the diagnosis A corresponding to the repaired portion and the incomplete failure diagnosis.

Here, the diagnosis B is not carried out in the latest state because the water temperature sensor is determined to be abnormal in the diagnosis A. However, the readiness code of the diagnosis B is set by the ECU, and this readiness code is read by the tool 23. Therefore, in the tool 23, the diagnosis B is not treated as an incomplete failure diagnosis. Therefore, the worker does not think that the diagnosis B is an incomplete failure diagnosis.

Therefore, the operator tries to drive the vehicle after repairing the water temperature sensor, but ends the operation of the vehicle when it is considered that the diagnosis A is completed in the ECU, and then again uses the tool 23 on the communication bus. There is a high possibility that the tool 23 will be connected to the 17 to perform the process of FIG.

Then, in this case, the tool 23 determines "NO" in S430, "YES" in S440, and determines that there is no failure in S450. Therefore, even if there is an abnormality in the diagnosis target (that is, the thermostat) of the diagnosis B, the abnormality is overlooked. That is, it is easy to cause insufficient confirmation of related functions after repairing the water temperature sensor.

Further, for example, it is assumed that the specific DTC and the readiness code are read by the tool 23 from the ECU of the comparative example in the state of the 2nd DC in FIG. 7 for the OBD vehicle inspection of the vehicle.
In this case, at least the specific DTC by the diagnosis A, the readiness code of the diagnosis A, and the readiness code of the diagnosis B are read from the ECU to the tool 23.

Therefore, the tool 23 determines "YES" in S520 of FIG. 5, and determines that the vehicle has failed in S550.
In this case, the operator can know that the water temperature sensor has an abnormality and the incomplete failure diagnosis based on the content displayed on the display of the tool 23, but in the tool 23, the diagnosis B is a diagnosis B. It is not treated as an incomplete failure diagnosis and does not appear on the display.

Therefore, the operator performs a test run of the vehicle after repairing the water temperature sensor, but as in the case of the vehicle inspection and maintenance described above, the operation of the vehicle is terminated when the diagnosis A is considered to be completed in the ECU. Probability is high.

Therefore, after that, when the worker connects the tool 23 to the communication bus 17 again and causes the tool 23 to perform the process of FIG. 5, the tool 23 determines "NO" in S520 and "YES" in S530. ", And in S540, it is determined to pass. Therefore, even if there is an abnormality in the thermostat that is the diagnosis target of diagnosis B, it will be passed. That is, the diagnosis B is not carried out in the latest state after the repair of the water temperature sensor, and there is a possibility that the vehicle should be rejected but passed.

[1-5] Effect Therefore, in the second diagnostic process of FIG. 3 performed by the microcomputer 3 in the ECU 1 of the present embodiment, the failure diagnosis result of the water temperature sensor by the first diagnostic process in S380, that is, the failure by the diagnosis A It is determined whether or not the diagnosis result is a result indicating an abnormality. When it is determined that the failure diagnosis result of the water temperature sensor is a result indicating an abnormality, the readiness code of the diagnosis B is cleared in S390.

(1a) In the ECU 1 of such an embodiment, as shown in FIG. 8 showing the same situation as in FIG. 7, when the water temperature sensor is determined to be abnormal by the diagnosis A at the 2nd DC, the readiness of the diagnosis B The code is cleared from memory 11. Therefore, for a thermostat whose failure diagnosis is performed on the condition that the water temperature sensor is determined to be normal, if the water temperature sensor becomes abnormal, the readiness code before the abnormality occurs remains in the memory 11. Can be prevented. Therefore, the DTC for the water temperature sensor is stored in the memory 11, and it becomes clear that the thermostat must be re-diagnosed when the water temperature sensor is repaired.

Therefore, when the DTC and readiness code stored in the memory 11 of the ECU 1 are read out and used for inspection and maintenance of the vehicle, it is possible to suppress insufficient confirmation after repair.
For example, it is assumed that the DTC and the readiness code are read by the tool 23 from the ECU 1 in the second DC state in FIG. 8 for inspection and maintenance of the vehicle.

In this case, at least the DTC by the diagnosis A and the readiness code of the diagnosis A are read from the ECU to the tool 23, but the readness code of the diagnosis B is cleared, so that the DTC is not read by the tool 23. Therefore, the tool 23 determines "YES" in S430 of FIG. 4, and in S470, at least the information indicating the diagnosis B is displayed on the display as the information indicating the incomplete failure diagnosis.

Then, the operator can know that the diagnosis B is an incomplete failure diagnosis. Therefore, after repairing the water temperature sensor corresponding to the detected DTC, the operator drives the vehicle (that is, a test run) until it is considered that not only the diagnosis A but also the diagnosis B is completed by the ECU 1. It will be. Then, assuming that the diagnosis A and the diagnosis B in the ECU 1 are determined to be normal, then, when the operator causes the tool 23 to perform the process of FIG. 4, the tool 23 determines "NO" in S430, and determines that the tool 23 is "NO". In S440, it is determined as "YES", and in S450, it is determined that there is no failure.

In this way, it is possible to suppress insufficient confirmation of the thermostat after repairing the water temperature sensor.
Further, when the specific DTC and the readiness code stored in the memory 11 of the ECU 1 are read out and used for the OBD inspection of the vehicle, it is possible to suppress the possibility of passing the vehicle which should be originally rejected.

For example, it is assumed that the specific DTC and the readiness code are read by the tool 23 from the ECU 1 in the second DC state in FIG. 8 for the OBD vehicle inspection of the vehicle.
In this case, at least the specific DTC by the diagnosis A and the readiness code of the diagnosis A are read from the ECU to the tool 23, but since the readiness code of the diagnosis B is cleared, they are not read by the tool 23.

Therefore, the tool 23 determines "YES" in S520 of FIG. 5, and determines that the vehicle has failed in S550, but the display shows that an abnormality has occurred in the water temperature sensor. At the same time, at least the information indicating the diagnosis B is displayed as the information indicating the incomplete failure diagnosis.

Therefore, after repairing the water temperature sensor, the operator will drive the vehicle (that is, test run) until it is considered that not only the diagnosis A but also the diagnosis B has been completed by the ECU 1. Then, assuming that the diagnosis A and the diagnosis B in the ECU 1 are determined to be normal, when the operator causes the tool 23 to perform the process shown in FIG. 5, the tool 23 determines "NO" in S520. In S530, it is determined as "YES", and in S540, it is determined as passing. Further, if the diagnosis B is not yet completed in the ECU 1 after the water temperature sensor is repaired, the tool 23 determines "NO" in S530 and determines in S550 that the diagnosis B fails.

As described above, if the diagnosis B is not performed after the water temperature sensor is repaired and the vehicle should be rejected, the possibility of being passed can be suppressed.
(1b) Further, in the ECU 1 of the above embodiment, the microcomputer 3 determines the failure diagnosis result by the first diagnosis process in the second diagnosis process for carrying out the diagnosis B, and the failure diagnosis result is abnormal. When it is determined that the result is shown, the readiness code of the diagnosis B is cleared.

According to such a configuration, the process for setting the readiness code of the diagnosis B and the process for clearing the readiness code are integrated into the same second diagnostic process. Therefore, it becomes easy to make the process for failure diagnosis and the software that realizes the process independent for each failure diagnosis, and it becomes easy to confirm the correctness of the process at the time of designing. In addition, it becomes easy to respond to design changes.

For example, a failure diagnosis such as diagnosis A, which is involved in the establishment of other diagnosis implementation conditions, is referred to as a higher-level diagnosis, and the higher-level diagnosis for diagnosis B is changed from diagnosis A to another diagnosis C, and The case where the diagnosis A is left is taken as an example. In this case, it is possible to deal with it only by changing the second diagnostic process. On the other hand, as in the second embodiment described later, the program may be configured to clear the readiness code of the diagnosis B in the first diagnosis process for carrying out the diagnosis A, but in the case of this configuration. , In the case of the above example, it may take some time to change the program. Specifically, from the process for executing the diagnosis A, the process for clearing the readiness code of the diagnosis B is deleted, and the process for executing the diagnosis C is for clearing the readiness code of the diagnosis B. It is sufficient to add a process, but there are multiple processes to be changed.

In the first embodiment, the water temperature sensor corresponds to a predetermined diagnosis target, the thermostat corresponds to another diagnosis target, the memory 11 corresponds to the storage unit, and the readiness code corresponds to the diagnosis history information. , DTC corresponds to the abnormality information. Then, the microcomputer 3 functions as a first diagnosis unit, a second diagnosis unit, and an erasing unit, respectively. S110 to S230 in FIG. 2 correspond to the processing as the first diagnostic unit, and S310 to S390 in FIG. 3 correspond to the processing as the second diagnostic unit. Then, S380 and S390 in FIG. 3 correspond to the processing as the erasing unit.

[2. Second Embodiment]
Since the basic configuration of the second embodiment is the same as that of the first embodiment, the differences will be described below. It should be noted that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description will be referred to.

In the ECU 1 of the second embodiment, as compared with the first embodiment, the microcomputer 3 performs the first diagnostic process of FIG. 9 instead of the first diagnostic process of FIG. Further, the microcomputer 3 performs the second diagnostic process of FIG. 6 described in the comparative example instead of the second diagnostic process of FIG.

In the first diagnostic process of FIG. 9, S240 is added as compared with the first diagnostic process of FIG. In the first diagnostic process of FIG. 9, the microcomputer 3 proceeds to S240 when the process of S160 or S190 is performed, that is, when the diagnosis A by the first diagnostic process determines an abnormality, and the microcomputer 3 proceeds to the diagnosis B. Clear the readiness code from the memory 11. Then, the process proceeds to S230.

That is, in the second embodiment, the program is configured to clear the readiness code of the diagnosis B in the first diagnosis process for carrying out the diagnosis A.
The effect of the above (1a) described for the first embodiment can also be obtained by such a second embodiment. Further, in order to clear the readiness code of the diagnosis B, it is not necessary to refer to or determine the failure diagnosis result by the first diagnosis process. Therefore, it is easy to simplify the process.

In the second embodiment, S110 to S240 in FIG. 9 correspond to the processing as the first diagnostic unit, and S310 to S370 in FIG. 6 correspond to the processing as the second diagnostic unit. And S240 of FIG. 9 corresponds to the processing as an erasing unit.

[3. Third Embodiment]
Since the basic configuration of the third embodiment is the same as that of the first embodiment, the differences will be described below. It should be noted that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description will be referred to.

In the ECU 1 of the third embodiment, as shown in FIG. 10, a diagnosis completion flag of diagnosis A and a diagnosis completion flag of diagnosis B are added as information processed by the microcomputer 3 as compared with the first embodiment. ing. As with the readiness code, each diagnosis completion flag has a set indicating the completion of the failure diagnosis and a non-set indicating the incompleteness of the failure diagnosis. Then, each diagnosis completion flag is also stored in the memory 11.

The diagnosis completion flag of diagnosis A is set when the readiness code of diagnosis A is set. The diagnosis completion flag of the diagnosis B is set when the readiness code of the diagnosis B is set, but is cleared under the same conditions as the condition in which the readiness code of the diagnosis B is cleared in the first embodiment. Further, the readiness code of the diagnosis B is not cleared when it is set, like the readiness code of the diagnosis A.

Therefore, in the ECU 1, the microcomputer 3 sets the readiness code of the diagnosis A and also sets the diagnosis completion flag of the diagnosis A in S230 of FIG.
Then, in S370 of FIG. 3, the microcomputer 3 sets the readiness code of the diagnosis B and also sets the diagnosis completion flag of the diagnosis B.

Further, in S390 of FIG. 3, the microcomputer 3 does not clear the readiness code of the diagnosis B, but clears the diagnosis completion flag of the diagnosis B.
Further, the microcomputer 3 transmits the DTC and readiness code for each diagnosis target and the diagnosis completion flags of the diagnoses A and B to the tool 23 in response to the read request from the tool 23. In the third embodiment, the diagnosis completion flag plays the same role as the readiness code in the first embodiment for the diagnoses A and B, so that the readiness codes of the diagnoses A and B are not transmitted to the tool 23. May be.

For the diagnosis A and B, the tool 23 treats the diagnosis completion flag as the readiness code in the first embodiment and processes it. For example, in the tool 23, the diagnosis A and B are determined to be completed or incomplete based on the diagnosis completion flag.

According to such a third embodiment, the same effect as that of the first embodiment can be obtained without clearing the readiness code in the ECU 1.
Further, the method of the third embodiment may be similarly applied to the second embodiment. In this case, in S240 of FIG. 9, the microcomputer 3 does not clear the readiness code of the diagnosis B, but may clear the diagnosis completion flag of the diagnosis B.

In the third embodiment, the diagnosis completion flags for the diagnoses A and B correspond to the diagnosis history information. Further, the diagnosis completion flag may be added only to the diagnosis B.
[4. Other embodiments]
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and can be variously modified and implemented.

For example, the diagnostic target by the first diagnostic process may be other than the water temperature sensor, and the diagnostic target by the second diagnostic process may be other than the thermostat. Further, for example, there may be a plurality of higher-level diagnoses for the diagnosis B. On the contrary, there may be a plurality of lower-level failure diagnoses performed on condition that the diagnosis A is determined to be normal.

Further, the ECU and its method described in the present disclosure are provided by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. It may be realized. Alternatively, the ECU 1 and its method described in the present disclosure may be realized by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the ECU and methods thereof described in the present disclosure are configured by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. It may be realized by one or more dedicated computers. The computer program may also be stored on a computer-readable non-transitional tangible recording medium as an instruction executed by the computer. Further, the method for realizing the functions of each part included in the ECU does not necessarily include software, and all the functions may be realized by using one or a plurality of hardware.

Further, a plurality of functions possessed by one component in the above embodiment may be realized by a plurality of components, or one function possessed by one component may be realized by a plurality of components. Further, a plurality of functions possessed by the plurality of components may be realized by one component, or one function realized by the plurality of components may be realized by one component. Further, a part of the configuration of the above embodiment may be omitted. Further, at least a part of the configuration of the above embodiment may be added or replaced with the configuration of the other above embodiment.

Further, in addition to the above-mentioned ECU, a system having the ECU as a component, a program for operating a computer as the ECU, a non-transitional actual recording medium such as a semiconductor memory in which this program is recorded, a diagnostic history storage method, etc. , The present disclosure can also be realized in various forms.

1 ... ECU, 3 ... Microcomputer, 11 ... Memory

Claims (3)

An electronic control device mounted on a vehicle
Memory unit (11) and
A failure diagnosis is performed for a predetermined diagnosis target, and when the failure diagnosis is completed, the diagnosis history information for the predetermined diagnosis target is stored in the storage unit, and the failure diagnosis determines that the predetermined diagnosis target is abnormal. In this case, the first diagnosis unit (S110 to S230, S110 to S240) configured to store the abnormality information about the predetermined diagnosis target in the storage unit, and
On condition that the predetermined diagnosis target is determined to be normal by the first diagnosis unit, a failure diagnosis is performed for another diagnosis target which is a diagnosis target different from the predetermined diagnosis target, and the failure is performed. When the diagnosis is completed, the diagnosis history information about the different diagnosis target is stored in the storage unit, and when the failure diagnosis determines that the different diagnosis target is abnormal, the abnormality information about the different diagnosis target is stored in the storage unit. The second diagnostic unit (S310 to S390, S310 to S370) configured to be stored in the unit, and
Erasing unit (S380, S390, S240) configured to erase the diagnosis history information about the other diagnosis target from the storage unit when the predetermined diagnosis target is determined to be abnormal by the first diagnosis unit. And, with
Electronic control device. The electronic control device according to claim 1.
The second diagnostic unit (S310 to S390)
It is determined whether or not the failure diagnosis result for the predetermined diagnosis target by the first diagnostic unit is a result indicating an abnormality (S380), and the failure diagnosis result for the predetermined diagnosis target indicates an abnormality. By erasing the diagnosis history information about the other diagnosis target from the storage unit (S390), it is configured to function as the erasing unit (S380, S390).
Electronic control device. The electronic control device according to claim 1.
The first diagnostic unit (S110 to S240) is configured to function as the erasing unit (S240).
Electronic control device.

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