File in Section:

Service Bulletin

Bulletin No.:
Date:

PI1190A
September, 2014

PRELIMINARY INFORMATION
Subject:

Sunroof Sunshade Binds and/or Will Not Retract Properly

Models:

2012-2015 Buick LaCrosse
2014-2015 Chevrolet Impala
Equipped with Sunroof (RPO C3U)
This PI has been revised to update the Models section. Please discard PI1190.

Condition/Concern
Some customers may comment that the sunroof sunshade binds or won’t retract properly.
The cause of this condition may be any of the following issues:

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•

Flutter containment patches on the rear crossmember may be sticking to the sunshade and impeding it’s travel
(2014 Impala only).

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•

Acoustic panels attached to the rear of the headliner may have partially detached (1) and/or bunched up (2)
putting too much tension on the sunshade roller.

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•

The rolled steel springs on the outboard ends of the sunshade may have become kinked or damaged due to
improper travel of the sunshade.

Recommendation/Instructions
Inspect the sunroof sunshade assembly for damage. If damage to the sunshade is evident, refer to the GM
electronic parts catalog (EPC) for the current sunshade service part and replace the sunshade following the steps
and tips below:
1. Fully open the sunroof sunshade.

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2. Run the front sunroof window to vent position and remove the rear sunroof window. Refer to Sunroof Window
Replacement - Rear in SI.
3. Power the sunshade to approximately halfway in the roof opening.
4. Lower the headliner. Refer to Headlining Trim Panel Replacement in SI.

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Note: The rearward crossmember retaining screw (circled in the graphic above) is also the retaining screw for the
forward fastener location of the sunshade end cap.
5. From the inside of the vehicle, remove the sunroof module rear crossmember by removing the two retaining
screws (1) located on each side. Do Not remove the sunshade end cap to module retaining screws yet.

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6. From the topside of the vehicle, remove the screw (1) from each end of the sunshade front bar that attaches the
shade to the drive cables.

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7. From inside the vehicle, remove the remaining two screws (1) that attach the sunshade end cap to the module
on both sides.
8. Remove the sunshade end caps from the sunshade.
9. Remove the sunshade from the sunroof frame rail tracks.
10. Remove all debris from the sunshade tracks by wiping them down with brake cleaner. Use an air nozzle to blow
out any remaining particles.
11. Check the rear rail tracks of the sunroof for damage by running a cotton ball, or equivalent, along the tracks.
12. Prior to sunshade installation, apply a dab of lubricant *RHEOSIL 500F, or equivalent, to the ends of the rail
tracks.
Important: Do Not unroll the sunshade prior to installation. The sunshade rewinding assembly is only designed to
be unrolled within the sunroof rail track system and can permanently damage if unrolled outside the sunroof rail
track.
13. With an assistant holding tension on the sunshade roll and positioning the opposite side, position one side of the
sunshade to the track.

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14. Start the inboard, downward tab (1) into the rail end then feed the metal clip into the lower rail track. Feed
approximately 25.4 mm (1.0 in), or slightly less, of the sunshade (2) into the track.
15. Have the assistant repeat step #14 on the opposite side.
16. Once both sides are started, manually roll out approximately 203-254 mm (8-10 in) of the sunshade. Work the
sunshade into the grease by dragging back and forth manually, ensuring both sides are sliding freely.

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Important: As shown in the graphic above, ensure that the tab of each end cap is fully seated into the rail end (1),
and that the sunshade material is properly positioned in the end cap and rail track (2).

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17. With one person holding the sunshade position/tension, have an assistant install the sunshade end cap
brackets (1) to the rail tracks, and install one of the rearward retaining screws (locations circled) on each side.
This will hold tension on the sunshade until the other rear end cap screw can be installed in a later step.
18. Manually pull the sunshade front bar up to the location of the shade drive cable attachments.

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Important: Before attaching the front bar screws, inspect for proper installation of the sunshade within the track.
When properly installed, the metal coil on the end of the sunshade (1) is BELOW the track (2). The graphic below
shows an example of incorrect installation; with the metal coil (1) positioned ABOVE the track (2).

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19. Install the screws (1) to the front bar of the sunshade and tighten to 2.5 Y (22 lb in).

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20. Install the remaining sunshade end cap to module rear screws, one to each side, and tighten all screws to 2.5 Y
(22 lb in).

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Note: The graphic above shows the current design crossmember, which has four hook and loop anti-rattle patches.
The patches are shown blue in color on the above example to improve viewing. These patches will be black on the
actual production crossmembers.
Important: Before reinstalling the rear crossmember, inspect that it is the current design. If these patches are not
evident, the crossmember is an earlier design and should be replaced with the service part listed in the part
table below.

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21. Position the rear crossmember to the vehicle, install two screws (1) to the rear crossmember located on each
side and tighten to 2.5 Y (22 lb in).

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Important: While cycling the sunshade, closely inspect for possible contact/interference between the motor wiring
harness (1) and the sunshade rollo fabric (2). It contact is evident, install an additional tie strap to hold the harness
away from the shade.
22. Slowly cycle the sunshade. Inspect the sunshade for binding and ensure proper operation.
23. Reinstall the rear sunroof window. Refer to Sunroof Window Replacement - Rear in SI.
24. Reinstall the headliner. Refer to Headlining Trim Panel Replacement in SI.
*We believe this source and their products to be reliable. There may be additional manufacturers of such products/
materials. General Motors does not endorse, indicate any preference for, or assume any responsibility for the
products or material from this firm or for any such items that may be available from other sources.

Parts Information
RHEOSIL 500F is not currently available from GMCC&A. You can obtain the product by calling TAI Lubricants at
302-326-0200. We recommend purchasing the 17.64 oz jar, which has enough grease to repair a large number of
vehicles.
Part Number

Description

23450831

MODULE ASM-SUN RF (Rear Crossbar)

Warranty Information
For vehicles repaired under warranty, use:
Labor Operation

Description

Labor Time

6041230

Sunroof Sunshade Replacement

Use Published
Labor
Operation Time