Engine Control Module (ECM) Power Relay Circuit High
Indicates an issue with the power relay circuit for the ECM.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The Engine Control Module (ECM) isn't getting the right voltage because of a problem in its power relay circuit—this could lead to performance issues or engine stalling.
What the computer is actually seeing
The ECM monitors the status of the power relay circuit, expecting to see a voltage between 12.0 to 14.5 volts when the engine is running. If the voltage is too high or too low, this code triggers.
What a healthy reading looks like
ECM voltage supply should be between 12.0V to 14.5V under normal operating conditions; at idle, voltage should stabilize around 13.5V.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the battery voltage; should be above 12.4V with the engine off and above 13.5V with it running. If low, charge the battery or check the alternator.
- 2Inspect the power relay and its connectors for corrosion, damage, or loose connections. Repair as needed.
- 3Test the power relay using a multimeter; measure resistance and operation when powered. Replace if it fails. Consider swapping with a similar relay if unsure.
- 4Check for continuity in the wiring from the relay to the ECM. Use a wiring diagram for pin locations. Repair or replace any damaged sections.
Common causes
- Faulty power relay
- Damaged wiring or connectors in the relay circuit
- Weak battery or alternator issues
- ECM failure
Typical repair cost
$$
Related codes
Frequently asked questions
Can I still drive with this code?
Yes, but you may experience poor drivability or stalling, so fix it soon.
Will this code come back after I clear it?
If the underlying issue isn't resolved, yes, it'll likely return after clearing.
Why does this code pair with others like P0562?
P0562 refers to general battery voltage issues, which can affect the power supply to the ECM, hence the correlation.
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