Rear Window Defogger Control Circuit Low
The rear window defogger circuit is reporting a low voltage condition.
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 system that clears the fog from your rear window isn't getting enough power to work right, which might be due to a bad connection or a problem with the defogger itself.
What the computer is actually seeing
The Body Control Module (BCM) sees a voltage drop (below 5 volts) on the rear window defogger control circuit when it should be receiving a voltage around 12 volts.
What a healthy reading looks like
The normal operating voltage for the rear window defogger should be around 12-14 volts when activated; if it's below 5 volts, this code will trigger.
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.
- 11. Inspect the wiring and connectors on the rear window defogger circuit for signs of damage, corrosion, or loose connections. Decision: Is there visible damage? If yes, repair/replace as needed; if no, continue.
- 22. Check the rear window defogger element for continuity using a multimeter. Expected value: should show low resistance (typically below 10 ohms). Decision: Does it show continuity? If yes, continue; if no, replace the defogger element.
- 33. Check the vehicle's fuses related to the rear window defogger circuit. Decision: Is the fuse intact? If no, replace the fuse and retest; if yes, continue.
- 44. Use a scan tool to check the BCM for fault codes or calibration issues. Decision: Are there BCM issues? If yes, follow diagnostic procedures for the BCM; if no, continue.
- 55. Measure voltage at the defogger control circuit when activated. Expected value: should be 12-14 volts. Decision: Is the voltage correct? If yes, suspect BCM; if no, there may be an issue in the wiring or the defogger element.
Common causes
- Faulty rear window defogger element
- Bad wiring or corroded connectors in the circuit
- Open circuit due to a blown fuse or broken wire
- Body Control Module (BCM) malfunction
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but you'll have a foggy rear window, which can impair visibility; fix it soon for safety.
Will this code come back if I clear it?
If the underlying issue isn't fixed, the code is likely to return.
Why does this code sometimes pair with other codes?
Intermittent issues in the electrical system can affect multiple components, leading to multiple codes.
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