Rear Light Control Module Fault
The rear light control module has detected a malfunction.
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)
This code means there's a problem with the module that controls the rear lights, like when a bulb is out or there's a wiring issue. The module expects a signal back from the lights that isn't happening.
What the computer is actually seeing
The rear light control module expects to receive certain voltage levels (usually around 12V) from the rear light circuits but isn't getting the expected feedback after a light control command is issued.
What a healthy reading looks like
The module should see about 12V at the rear light harness when activated. If a bulb is blown, resistance could rise instead of the expected voltage drop, showing 0V instead.
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 rear light bulbs for any blown filaments; replace if necessary. Decision Point: Are the bulbs good?
- 2Inspect the wiring harness for damage or corrosion. Decision Point: Is wiring intact?
- 3Test the voltage at the rear light harness while activating the lights (should be approximately 12V). Decision Point: Is voltage present?
- 4Examine connectors for corrosion or looseness. Decision Point: Are connectors secure?
- 5If all checks are good and the problem persists, consider a faulty rear light control module.
Common causes
- Blown rear bulb(s)
- Corroded or damaged wiring
- Faulty rear light control module
- Poor ground connection
- Loose connectors
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally safe to drive, but you may have non-functioning rear lights, which could be a safety hazard.
Will this code come back after clearing?
If the underlying issue isn't fixed, yes, it will likely return.
Can this code be caused by other electrical issues?
Yes, any problem affecting the electrical system including shorts or opens in wiring can trigger this code.
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