DTC P0685 ECM/Pcm Power Relay Control Circuit / Open: DTC Detecting Condition

DTC DETECTION CONDITION CHART

Item	Detecting Condition	Possible cause
DTC Strategy	Detects a short to ground, to battery or open circuit on the main relay	Poor Connection Open or short in control circuit. Main Relay PCM
Enable Conditions	Engine Running 11V ≤ Ignition Voltage ≤ 16V Enable Time delay ≥ 0.5 sec.
Threshold value	Open or Short
Diagnosis Time	Continuous (More than 5 sec. Failure for every 10 sec. test)
MIL On Condition	DTC only (NO MIL ON)

If Main relay has a fault (ex. Open) under engine running, the DTCs, P0638/P0685/P1295/P2106, can happen at the same time.

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