Electronic control apparatus for vehicle and control method for vehicle

1. An electronic control apparatus using a battery as a power source, for a vehicle in which an engine is installed, comprising:

a plurality of processing circuits;

power supply shut-off circuits shutting off the power supply to certain processing circuits of said plurality of processing circuits; and

a control circuit controlling said power supply shut-off circuits based on an ON/OFF signal for an ignition key, to shut off the power supply to said certain processing circuits after an operation of said engine is stopped by means of turning off said ignition key.

2. An electronic control apparatus for a vehicle according to claim 1 ,

wherein said certain processing circuits are unnecessary for the process to be performed after the operation of said engine is stopped.

3. An electronic control apparatus for a vehicle according to claim 2 ,

wherein said process to be performed after the operation of said engine is stopped, is started from an elapse of a standby time after the operation of said engine was stopped.

4. An electronic control apparatus for a vehicle according to claim 3 , further comprising;

timer circuits shutting off the power supply to the processing circuit, which is used for said process to be performed after the operation of said engine is stopped, of said plurality of processing circuits, during a period until said standby time has elapsed after the operation of said engine was stopped, and resuming the power supply at the time when said standby time has elapsed.

5. An electronic control apparatus for a vehicle according to claim 2 ,

wherein said engine is provided with a fuel vapor purge system, and

said process to be performed after the operation of said engine is stopped, is the process of diagnosing whether or not the leakage occurs in said fuel vapor purge system.

6. An electronic control apparatus for a vehicle according to claim 5 ,

wherein it is diagnosed whether or not the leakage occurs in said fuel vapor purge system, based on a pressure in a diagnosis section detected by a pressure sensor.

7. An electronic control apparatus for a vehicle according to claim 6 ,

wherein said plurality of processing circuits includes a monitoring circuit monitoring a signal output from said pressure sensor, and

said power supply shut-off circuits shut off the power supply to the processing circuits other than said monitoring circuit, of said plurality of processing circuits.

8. An electronic control apparatus for a vehicle according to claim 2 ,

wherein said electronic control apparatus self-shuts off the power supply from said battery at the time when the process to be performed after the operation of said engine is stopped, is completed.

9. An electronic control apparatus using a battery as a power source, for a vehicle in which an engine is installed, comprising:

a plurality of processing means;

power shut-off means for shutting off the power supply to certain processing means of said plurality of processing means; and

control means for controlling said power shut-off means based on an ON/OFF signal for an ignition key, to shut off the power supply to said certain processing means after an operation of said engine is stopped by means of turning off said ignition key.

10. A control method of using a plurality of processing circuits which uses a battery as a power source, for a vehicle in which an engine is installed, comprising the steps of:

receiving an ON/OFF signal for an ignition key; and

judging whether or not an operation of said engine is stopped, based on the ON/OFF signal for said ignition keys,

when it is judged that the operation of said engine is stopped,

shutting off the power supply to certain processing circuits of said plurality of processing circuits; and

using the processor circuit, other than said certain processing circuits, of said plurality of processing circuits, to execute a process to be performed after the operation of said engine is stopped.

11. A control method for a vehicle according to claim 10 ,

wherein said step of shutting off the power supply to said certain processing circuits shuts off the power supply to the processing circuits unnecessary for the process to be performed after the operation of said engine is stopped.

12. A control method for a vehicle according to claim 10 ,

wherein said step of executing the process to be performed after the operation of said engine is stopped, comprises the steps of:

measuring an elapse of a standby time after the operation stop of said engine; and

starting the process to be performed after the operation of said engine is stopped, after said standby time has elapsed.

13. A control method for a vehicle according to claim 10 ,

wherein said step of executing the process to be performed after the operation of said engine is stopped, further comprises the steps of:

shutting off the power supply to the processing circuit, which is used for the process to be performed after the operation of said engine is stopped, during a period until said standby time has elapsed after the operation of said engine was stopped; and

resuming the power supply to the processing circuit, which is used for the process to be performed after the operation of said engine is stopped, at the time when said standby time has elapsed.

14. A control method for a vehicle according to claim 10 ,

wherein said engine is provided with a fuel vapor purge system, and

said step of executing the process to be performed after the operation of said engine is stopped, comprises the step of diagnosing whether or not the leakage occurs in said fuel vapor purge system after the operation of said engine is stopped.

15. A control method for a vehicle according to claim 14 ,

wherein said step of diagnosing whether or not the leakage occurs in said fuel vapor purge system, comprises the steps of:

detecting a pressure in a diagnosis section in said fuel vapor purge system; and

diagnosing whether or not the leakage occurs based on the pressure in said diagnosis section.

16. A control method for a vehicle according to claim 15 ,

wherein said plurality of processing circuits includes a monitoring circuit monitoring the pressure in said diagnosis section, and

said step of shutting off the power supply comprises the step of shutting off the power supply to the processing circuits other than said monitoring circuit, of said plurality of processing circuits.

17. A control method for a vehicle according to claim 10 , further comprising the step of self-shutting off the power supply from said battery at the time when the process to be performed after the operation of said engine is stopped, is completed.