Back Up Power Source Circuit
CIRCUIT DESCRIPTIONBattery voltage is supplied to terminal BATT of the ECM even when the ignition switch is OFF for use by the diagnostic trouble code memory and air-fuel ratio adaptive control value memory, etc.
HINT: If DTC P1600 appears, the ECM is not able to store another diagnostic trouble code.
ECM Back-up Power Supply Circuit:
WIRING DIAGRAM
INSPECTION PROCEDURE