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.
Timer Function
The rear window defogger system is controlled by the BCM.
Power is supplied at all times
- through 20A fuse[No.10, located in the fuse block (J/B)]
- to the rear window defogger and door mirror defogger relay terminal No.6, and
- through 20A fuse[No.11, located in the fuse block (J/B)]
- to the rear window defogger and door mirror defogger relay terminal No.3.
With the ignition switch in the ON or START position, power is supplied
- through 10A fuse[No. 1, located in the fuse block (J/B)]
- to BCM terminal NO.68
- to the rear window defogger and door mirror defogger relay terminal No.1, and When the rear defogger switch in the multifunction switch is ON, ground is supplied
- through terminal No.5 of the multifunction switch
- to BCM terminal No. 10.
Terminal No. 144 of the BCM then supplies ground to the rear window defogger and door mirror defogger relay terminal No. 2.
With power and ground supplied, the rear window defogger and door mirror defogger relay is energized to operate rear window defogger for about 15 minutes.
When the system is activated, the rear window defogger indicator in the rear defogger switch illuminates.
Power is supplied
- from rear window defogger and door mirror defogger relay terminal No. 5 and No. 7
- to multifunction switch terminal No. 6.
Use the Manual With the Right Hardware
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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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