P0603
P0603 ECM Power SupplyComponent Description
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.
On Board Diagnosis Logic
P0603:
DTC Confirmation Procedure
NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
1. If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next step.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON, wait at least 10 seconds.
3. Turn ignition switch OFF, wait at least 5 minutes.
4. Turn ignition switch ON, wait at least 10 seconds.
5. Repeat steps 2 to 3 for 5 times.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to [P0603 ECM Power Supply].
Diagnosis Procedure
