Battery voltage is supplied to the ECM even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc.
DTC Logic
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE 1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds. >> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
Turn ignition switch ON and wait at least 1 second.
Start engine and let it idle for 1 second.
Turn ignition switch OFF, wait at least 10 seconds, and then turn it ON.
Repeat steps 2 and 3 for 4 times.
Check 1st trip DTC. Is 1st trip DTC detected?
YES >> Go to Diagnosis Procedure.
NO >> Inspection END
Diagnosis Procedure 1.CHECK ECM POWER SUPPLY
Turn ignition switch OFF.
Disconnect ECM harness connector.
Check the voltage between ECM harness connector and ground.
Is the Inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2. 2.DETECT MALFUNCTIONING PART
Check the following.
15 A fuse (No. 42)
IPDM E/R harness connector F10
Harness for open or short between ECM and battery >> Repair or replace harness or connectors.
