Possible causes include:
* Faulty PCM power relay: The relay itself might be stuck open or closed, or internally damaged.
* Wiring problems: Damaged, corroded, or loose wiring in the circuit leading to the PCM relay. This could include the relay's power supply wires, ground wires, or connections.
* Fuse issues: A blown fuse in the circuit could also prevent power from reaching the relay.
* PCM failure: While less likely, a faulty PCM could also trigger this code. However, this is usually diagnosed after checking the other possibilities.
To diagnose this code, a mechanic will likely check the relay, the wiring for shorts or breaks, and related fuses. A scan tool will help verify the code and see if other codes are present that might point to the root cause. Replacing the relay is often the first step in troubleshooting.
