Faulty Engine Control Module (ECM) Power Supply
Indicates a problem with the power supply to 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 ECM isn't getting reliable power to operate, which can cause the engine to not start or run poorly.
What the computer is actually seeing
The ECM is detecting an unexpected voltage level, usually below 8 volts or higher than 16 volts at its power supply circuits.
What a healthy reading looks like
Power supply voltage should be between 9 and 16 volts while the engine is running.
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 battery voltage; it should read between 12.4V to 12.7V with engine off and at least 13.5V with engine running.
- 2Inspect the ground connections for the ECM, ensuring they're clean and tight.
- 3Confirm the power supply connections to the ECM; look for corroded terminals or damage.
- 4Check for breaks or shorts in the wiring between the power source and the ECM.
- 5If all checks are good, the ECM may need to be replaced or reprogrammed.
Common causes
- Faulty ECM
- Bad power or ground connections
- Wiring issues or shorts in the harness
- Faulty battery or charging system
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, it's not safe; the engine may stall or not start at all.
Will the code come back after clearing?
It may return if the underlying issue isn't resolved.
Why does this code appear with other codes?
This code often pairs with others indicating electrical or module issues that impact engine management.
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