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 Defogger System does not Operate: Description
When the rear window defogger switch is turned on, a rear window defogger activation request signal is sent via the CAN communication line to the air conditioning amplifier. Then the air conditioning amplifier operates the rear window defogger. When the on signal from the switch is received, the defogger relay (DEFOG) is operated for 15 minutes. Also, if the off signal from the switch is received within 15 minutes, the defogger relay (DEFOG) operation is stopped.
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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.
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