Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Rear Window Defog/Heated Mirror
The defroster button located on the HVAC control controls the rear window defogger and the heated side view mirrors.
When the defroster button is pushed, the HVAC control sends a bus message over the PCI bus to the Front Control Module (FCM) which controls the Rear Window Defogger relay. The defroster LED will illuminate when the defroster function is on. The defroster will function for 10 minutes or can be cycled off sooner by pressing the defroster button again.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.