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.
2004 Infiniti M45FACTORY OEM SERVICE PROCEDURE
4. Check Rear Window Defogger Input Signal Circuit For Open Or Short
- Stop engine.
- Disconnect rear window defogger and door mirror defogger relay.
- Disconnect combination meter harness connector.
- Check harness continuity between rear window defogger and door mirror defogger relay terminals 5, 7 and combination meter terminal 25.
Refer to WIRING DIAGRAM .
Continuity should exist.
- Also check harness for short to ground and short to power.
OK or NG
- OK: GO TO 6. CHECK COMBINATION METER .
- NG: GO TO 5.
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.