ECM/PCM Power Supply Voltage
The power supply voltage to the ECM/PCM is out of the normal range.
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 amount of voltage, which can cause performance issues.
What the computer is actually seeing
The ECM sees a voltage above or below the specified range, typically under 10V or above 16V.
What a healthy reading looks like
Normal operating voltage is between 12V to 14.5V for most diesel applications.
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 with a multimeter; should be 12V-14.5V. If not, repair or replace the battery.
- 2Inspect all battery connections for corrosion or looseness.
- 3Verify the ground connections; clean and tighten as necessary.
- 4Check for any damaged wiring harnesses leading to the ECM.
- 5Measure the voltage at the ECM connector; if it’s out of expected range, identify the wiring fault.
Common causes
- Faulty ECM/PCM
- Bad battery connections
- Corroded wiring or connectors
- Defective voltage regulator
- Bad alternator output
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderate severity; it may cause drivability issues, so fix it soon.
Will this code return after clear?
Yes, if the underlying issue isn't fixed, it will return.
Can this code be related to other symptoms?
Yes, issues like stalling or loss of power may accompany this code.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
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