B0290
Rear Defrost Switch Circuit
The body control module has detected a fault in the rear window defroster switch circuit. The switch may be stuck or its signal does not reach the module — the rear defroster cannot be activated.
The body control module has detected a fault in the rear window defroster switch circuit. The switch may be stuck or its signal does not reach the module — the rear defroster cannot be activated.
Common causes
- high
Defrost switch failed
One of the most commonly reported causes for this code — check this first.
Typical part cost: $30-220
- medium
Wiring or connector fault
A plausible cause — test and verify before replacing parts.
Typical part cost: $30-220
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does B0290 mean?
B0290 means "Rear Defrost Switch Circuit". It is a generic OBD-II code that points to a fault in the body.
What are the most common causes of B0290?
defrost switch failed; wiring or connector fault — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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