DTC P0685-00: Main Relay Control Circuit Open: Notes

DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0685:00	Main relay control circuit open
DETECTION CONDITION	This DTC sets when the ignition switch position run circuit indicates the key is in the off, ACC, or LOCK position, and the amount of time the PCM remains powered through the PCM power relay exceeds a predetermined amount of time. Diagnostic support note  This is a continuous monitor (CCM). The check engine light illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle. FREEZE FRAME DATA (Mode 2)/Snapshot data is available. The DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	-
POSSIBLE CAUSE	Main relay malfunction Short to ground or open circuit in main relay power supply circuit: Short to ground in wiring harness between MAIN 200 A fuse and main relay terminal D MAIN 200 A fuse and/or ENG.MAIN 40 A fuse malfunction Open circuit in wiring harness between battery positive terminal and main relay terminal D ENGINE2 15 A fuse malfunction Short to ground in wiring harness between the following terminals: Main relay terminal C-PCM terminal 2S Main relay terminal C-PCM terminal 2T PCM connector or terminals malfunction Open circuit in wiring harness between PCM terminal 1BZ and body ground Open circuit in wiring harness between PCM terminal 2AA and body ground Open circuit in wiring harness between the following terminals: Main relay terminal C-PCM terminal 2S Main relay terminal C-PCM terminal 2T PCM malfunction