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.
2005 Acura MDX BaseFACTORY OEM SERVICE PROCEDURE
Function Test: Defogger
- Connect the No. 3 and No. 6 terminals with a jumper wire, and check for voltage between the No. 3 terminal and body ground. There should be battery voltage and both mirrors should warm up with the ignition switch ON (II).
- If there is no voltage or neither warms up, check for:
- - an open in the ORN and ORN/WHT wires.
- - blown No. 4 (7.5 A) fuse in the driver's under-dash fuse/relay box.
- - poor ground (G601, G651).
- If only one fails to warm up, check its defogger.
- If both warm up, check the defogger switch.
- If there is no voltage or neither warms up, check for:
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.