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.
2007 Lexus RX 350 FWDFACTORY OEM SERVICE PROCEDURE
Rear Window Defogger System Does Not Operate: Description
- The rear defogger & mirror heater switch on the multi-display inputs a request signal to the A/C amplifier (ECU). Then, the A/C amplifier turns ON the RR-DEF relay built into the power distributor in response to the input, thus switching ON the rear defogger. (The deicer and mirror heater also turn ON at the same time.)
HINT:
The power distributor is built into the J/B No. 2.
- The RR-DEF relay is built into the J/B No. 2. For inspection, use the terminals in the J/B No. 2.
- If RR-DEF relay is malfunctioning, replace the J/B No. 2.
Factory Service Tools
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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.