Pinpoint Test B: Powertrain Control Module (Pcm) Power Relay
WARNING: This page is about a different car, the 2023 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
Refer to ELECTRONIC ENGINE CONTROLS - 3.3L TIVCT for schematic and connector information.
Normal Operation and Fault Conditions
Refer to the DTC Fault Trigger Conditions below.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Condition |
|---|---|---|
| PCM P0685:00 | ECM/PCM Power Relay Control Circuit/Open: No Sub Type Information | Sets when the ISP-R circuit indicates the ignition is in the OFF, ACC, or LOCK mode, and the amount of time the PCM remains powered through the PCM power relay exceeds a predetermined amount of time. Ability to communicate with the PCM when the ignition is in the OFF, ACC, or LOCK mode indicates a hard fault. |
| PCM P068A:00 | ECM/PCM Power Relay De-Energized - Too Early: No Sub Type Information | Sets when the non volatile random access memory write did not complete successfully after the ignition key was turned OFF, prior to PCM shutdown. This DTC also sets when the PCM power relay is de-energized too early. |
Possible Sources
- PCM power circuitry concern
- PCM power relay (12A646)
- PCM (12A650)
For testing procedures refer to PINPOINT TESTS B: POWERTRAIN CONTROL MODULE (PCM) POWER RELAY