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Window Begins Down Operation During Up Operation

  1. Sliding Resistance Check

    Turn ignition on. When performing one-touch or manual UP operation, observe glass in window guides. If problem causing resistance increase is visible, repair or replace problem as necessary and go to next step. If problem causing resistance is not visible, go to next step.

  2. Reset Window Motor Limit Switch

    With window motor harness connector connected, rotate motor for 4-5 seconds in upward direction (top dead center of door glass). Check operation of power window. If power window does not operate properly, go to next step. If power window operates properly, system is okay at this time.

  3. Sliding Resistance Check With Regulator Assembly Removed

    Remove window motor and regulator assembly. See WINDOW MOTOR & REGULATOR ASSEMBLY  under REMOVAL & INSTALLATION. Raise glass by hand while observing glass in window guides. If glass moves smoothly in window guides, go to next step. If glass does not move smoothly in window guides, repair window guides or frame. Retest system operation.

  4. Check System After Replacing Driver Door ECU

    Ensure window motor and regulator operate smoothly. Replace driver door ECU. Install window motor and regulator assembly. With window motor harness connector connected, rotate motor for 4-5 seconds in upward direction (top dead center of door glass). Check operation of power window. If power window does not operate properly, window motor is faulty. If power window operates properly, original driver door ECU is faulty.
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