Code result
B0290
Rear Defrost Switch Circuit
Moderate severity
What it means
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.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Defrost switch failed
highOne of the most commonly reported causes for this code — check this first.
Wiring or connector fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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