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.
Door Control Unit Input Test
Remove master power window switch from driver's door. See MASTER POWER WINDOW SWITCH under REMOVAL & INSTALLATION. Disconnect 20-pin harness connector. Inspect connector terminals for damage or corrosion. Repair or replace as necessary, then retest system. If connections are okay, using a DVOM, perform driver's control unit input test. See Fig 1 or Fig 2 . On Prelude, if all input tests are okay, replace door multiplex control unit.
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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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