Glow Plug Control Module Circuit Malfunction
There's a problem with the glow plug control module circuit.
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 glow plug control module helps heat up the glow plugs, which need to be hot for starting a diesel engine in cold conditions. If there's a fault in this circuit, the engine might not start well or at all when it's cold.
What the computer is actually seeing
The engine control module (ECM) is monitoring the voltage and resistance across the glow plug control circuit. It expects a certain range of values when the glow plugs are activated. A failure in this circuit can trigger the code.
What a healthy reading looks like
When the glow plugs are activated, the voltage on the control circuit should generally be around 12V; resistance should typically be below 5 ohms.
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.
- 1Inspect the condition of the wiring and connectors on the glow plug control module for damage or corrosion.
- 2Check the fuse for the glow plug system to ensure it isn't blown.
- 3Measure the voltage at the glow plug control module when the ignition is turned on; it should be around 12V. If not, investigate power supply issues.
- 4Check the resistance of the glow plugs with a multimeter; they should be under 5 ohms. If any are faulty, replace them and retest the system.
- 5If all checks are good, replace the glow plug control module and clear the fault code.
Common causes
- Faulty glow plug control module
- Damaged wiring or connectors
- Blown fuse related to the glow plug system
- Faulty glow plugs themselves
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
You can drive the vehicle, but be aware it may have poor cold starting performance.
Will this issue come back after clearing the code?
If the underlying issue isn't fixed, it likely will return.
Why is this code paired with other glow plug codes?
These codes often indicate problems in the same system affecting the glow plugs.
Working a real vehicle right now?
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