Liftgate or Liftgate Glass Binds, Does Not Open Completely, CHMSL Hits Roof (Remove Material from CHMSL Applique)

Some customers may comment that the liftgate or liftgate glass binds when opening or does not open all the way.

This condition is caused by the Center High Mounted Stop Lamp (CHMSL) applique hitting the roof of the vehicle.

Verify that the CHMSL applique is not loose or broken off one or more of its mounting points. If the applique is broken, it will be necessary to order a replacement part.

Important: 

To achieve the proper clearance, modification to the applique is required using the following procedure:

1. Measure (with applique installed) the area of interference in order to determine the material to be removed.

•	The top surface (height) of the applique should line up approximately 1 mm (0.039 in) below the top surface of the roof.

•	A gap of 6-8 mm (0.236-0.315 in) should exist between the roof and the applique to allow for adequate clearance while opening the liftgate.

Before Modification:




2. Mask off the desired amount of material to be removed.
3. Open the liftgate glass.

Notice: Do no damage the applique or the lifgate glass when removing the applique from the liftgate glass.

4. Remove the screws that retain the applique to the liftgate glass.
5. With a flat-bladed tool, carefully remove the applique from the liftgate glass.
6. Remove the CHMSL harness grommet from the roof panel.
7. Disconnect the CHMSL harness connector and remove CHMSL applique from the vehicle.
8. Using a 1/4" die grinder and Scotch-Brite® Disc, 3M® P/N 07481, remove excess material from the applique.

After Modification:




9. Paint the applique to match.

Important: If the original part is used, it is important to seal (clear coat) the edge to protect the clear coat from lifting.

10. Remove the old adhesive from the underside of the applique.
11. Clean the application area of the CHMSL applique with Isopropyl Alcohol (rubbing alcohol), 3M® P/N 08984, or equivalent, and dry thoroughly using a clean low lint towel or towelette.
12. Apply double-sided adhesive tape, 3M® P/N 06397, or equivalent, to the underside of the CHMSL applique.
13. Remove the old adhesive from the liftgate glass.

Important: 

•	The installation area of the liftgate glass must be clean and dry. Any airborne dust, oils, etc., may contaminate the glass or the applique adhesive, and reduce the bond of the tape.

•	DO NOT use commercial glass or surface cleaners. These may contain petroleum.

•	The glass surface temperature should be no lower than 21°C (70°F) and not exceed 38°C (100°F).

14. Clean the application area of the liftgate glass with Isopropyl Alcohol (rubbing alcohol), 3M® P/N 08984, or equivalent, and dry thoroughly using a clean low lint towel or towelette.
15. Apply adhesive promoter, P/N 12378555, in Canada, use P/N 88901239, to the liftgate glass surface, completely wetting the applique application area.

Important: 

•	Use a clean low lint towel or towelette and wipe the glass, only removing the excess adhesive promoter from the lift gate glass.

•	Do not wipe the glass dry.

•	Allow the liftgate glass to air dry completely.

•	The applique must be installed within 30 minutes following the use of the promoter.

16. Allow the adhesive promoter to remain on the glass surface for a minimum of 10 seconds.
17. Attach the CHMSL wire to the connector and install the grommet.
18. Slide the liftgate glass on the hinge pins to the left in order to allow clearance for the locating hooks.
19. Remove the protective liner from the tape on the applique.
20. Attach the locating hooks on the applique to the hinge pins.
21. Apply the applique to the liftgate glass.
22. With the heel of your hand, and starting from center of the applique and working outward towards each outer edge, apply even and consistent pressure ensuring complete contact of the adhesive strip to the glass.
23. Install the screws that retain the applique to the liftgate glass.

Tighten
Tighten the screws to 5 N·m (44 lb in).

Important: The vehicle must be kept dry and at 21°C (70°F) to 43°C (110°F) for no less than 4 hours to ensure proper adhesive cure time.

24. Clean the liftgate glass and applique area.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use: