Window drops down — Service Bulletin Fix

Learn how to fix a Window drops down condition and an Open Then Close Driver Window message on the dash

GM has issued a service bulletin #21-NA-046 to address an issue where the window drops down about 1/4″ or more, causing wind noise. The window movement occurs when using the sound system in the vehicle and directly after a high volume/high bass event. The event may be followed by a dash warning message advising you to Open Then Close Driver Window.

Vehicles affected by GM service bulletin #21-NA-046

2018-21 GMC Terrain & Chevrolet Equinox
2018-2020 Holden & Equinos

Cause of the window issues

GM has determined that the high volume/high bass event in the speaker in the door can cause the power window motor armature to move slightly due to the vibration. That movement causes the window to lose its home memory.

Window drops down — how to fix the problem

The fix is easy, but it requires removing the door trim panel to access the power window motor.

1) Remove the door trim panel
2) Peel off a section of the water deflector barrier in order to access the window motor
3) You will need adhesive-backed closed-cell 1/4″ thick dense foam to perform the fix (Kent Automotive #83327).
4) Cut the foam into two 1″ squares. Peell the silicone liner off of one square and place the square on top of the other square to form a 1/2″ thick block of foam
5) Clean the inside of the door panel so the adhesive can stick
6) Apply the foam block (1) to the to inside of the inner door panel (2), so it will insulate the motor housing from vibrations coming from the door panel.
7) Reinstall the water deflector
8) Reinstall the door trim panel
9) Perform the power window motor relearn procedure listed below

Single Window Motor Relearn Procedure

Note: This procedure must be performed with the doors closed.
1) Turn the ignition to the ON position.
2) Starting with the window completely UP, press and hold the power window switch until the window is fully open and continue holding the switch down for approximately 5 seconds after the window is completely open.
3) Pull the power window switch up until the window is fully closed and continue holding the switch up for approximately 5 seconds after the window is completely closed.
The window should now be programmed and the window should perform the express up and express down functions and should index normally when the door is opened and closed.