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.
Component Testing
Rear Defogger Relay Test
- Ignition OFF, disconnect the KR5 Rear Defogger Relay or the KR4B Outside Rear View Mirror Heater Relay.
- Test for 60-180 Ω between terminals 85 and 86.
- If less than 60 Ω or greater than 180 Ω
Replace the KR5 Rear Defogger Relay or the KR4B Outside Rear View Mirror Heater Relay.
- Go to next step: If between 60-180 Ω
- If less than 60 Ω or greater than 180 Ω
- Test for infinite resistance between the terminals listed below:
- 30 and 86
- 30 and 87
- 30 and 85
- 85 and 87
- If less than infinite resistance
Replace the KR5 Rear Defogger Relay or the KR4B Outside Rear View Mirror Heater Relay.
- Go to next step: If infinite resistance
- Install a 3 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.
- Test for less than 2 Ω between terminals 30 and 87.
- If 2 Ω or greater
Replace the KR5 Rear Defogger Relay or the KR4B Outside Rear View Mirror Heater Relay.
- Go to next step: If less than 2 Ω
- If 2 Ω or greater
- All OK
NO RELATED
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.