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.
Diagnosis Procedure
Regarding Wiring Diagram information, refer to "WIRING DIAGRAM ".
- CHECK ENCODER OPERATION
- Turn ignition switch ON.
- Check signal between main power window and door lock/unlock switch connector D7 terminal 3 and ground with oscilloscope.
Main power window and door lock/unlock switch Ground Signal (Reference value) Connector Terminal D7 3 - Is the inspection result normal?
YES: Replace main power window and door lock/unlock switch. Refer to "REMOVAL AND INSTALLATION ".
NO: GO TO 2
- CHECK ENCODER SIGNAL CIRCUIT
- Turn ignition switch OFF.
- Disconnect main power window and door lock/unlock switch and front power window motor LH connectors.
- Check continuity between main power window and door lock/unlock switch connector D7 terminal 3 and front power window motor LH connector D9 terminal 5.
Main power window and door lock/unlock switch Front power window motor LH Continuity Connector Terminal Connector Terminal D7 3 D9 5 Yes - Check continuity between main power window and door lock/unlock switch connector D7 terminal 3 and ground.
Main power window and door lock/unlock switch Ground Continuity Connector Terminal D7 3 - No Is the inspection result normal?
YES: GO TO 3
NO: Repair or replace harness.
- CHECK ENCODER POWER
- Connect main power window and door lock/unlock switch connector.
- Turn ignition switch ON.
- Check voltage between front power window motor LH connector D9 terminal 2 and ground.
Front power window motor LH Ground Voltage Connector Terminal D9 2 - Battery voltage Is the inspection result normal?
YES: GO TO 5
NO: GO TO 4
- CHECK ENCODER POWER CIRCUIT
- Turn ignition switch OFF.
- Disconnect main power window and door lock/unlock switch.
- Check continuity between main power window and door lock/unlock switch connector D7 terminal 4 and front power window motor LH connector D9 terminal 2.
Main power window and door lock/unlock switch Front power window motor LH Continuity Connector Terminal Connector Terminal D7 4 D9 2 Yes - Check continuity between main power window and door lock/unlock switch connector D7 terminal 4 and ground.
Main power window and door lock/unlock switch Ground Continuity Connector Terminal D7 4 - No Is the inspection result normal?
YES: Replace main power window and door lock/unlock switch. Refer to "REMOVAL AND INSTALLATION ".
NO: Repair or replace harness.
- CHECK ENCODER GROUND
- Turn ignition switch OFF.
- Check continuity between front power window motor LH connector D9 terminal 4 and ground.
Front power window motor LH Ground Continuity Connector Terminal D9 4 - Yes Is the inspection result normal?
YES: Replace front power window motor LH. Refer to "REMOVAL AND INSTALLATION ".
NO: Repair or replace harness.
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.
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