Body - Vario Roof(R) Cracking Noises During Operation

Date: September 15, 2006
Order No.: P-B-77.33/45
Supersedes:
Group: 77

SUBJECT:
Model 171.454/456/473

Cracking Noise from Pivot 1 on Vario Roof Frame

If you receive customer reports in the above model vehicles regarding a cracking noise from the Vario Roof frame when driving on rough roads or when standing near the C-pillar area after actuating the roof, this may be due to the shim and safety clip binding against the rough surface coating on the frame. After the roof is actuated and completes the cycle, the pressure in the hydraulic system slowly decreases and roof frame settles in to its normal location. It is during this final motion that the noise can most clearly be heard. To resolve, perform the below procedure.

1. Lower Vario Roof and leave trunk lid open and the rear shelf in the vertical position.

2. Remove safety clip (Figure 1, Pos. 1) and shims (Figure 1, Pos. 2) from Vario Roof frame control arm (Figure 1, Pos. 4).

3. Clean contact surfaces of safety clamp, shims and roof frame with Degreaser.

4. Apply lubricant to safety clamp, shims and roof frame where these parts contact each other.

5. Push control arm (Figure 1, Pos. 4) slightly inward and apply lubricant to pin (Figure 1, Pos. 3).





6. Reinstall shims (Figure 1, Pos. 2) and safety clip (Figure 1, Pos. 1).

7. Cycle roof several times while to insure noise is no longer present. Stand near C-pillar immediately after roof completes the opening and closing cycles to best hear the cracking noise.

Note:
This repair is non-time claimable under Group 77.





Parts Information