Service bulletin LI77.20-P-073486

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NHTSA's summary

Complaint Water ingress at the sliding sunroof can lead to moisture in the interior. In some cases, the leakage may also be visible to the customer in the area of the overhead control panel. Cause The following causes can lead to water ingress in the area of the sliding sunroof and thus to moisture in the vehicle interior: 1. Incorrectly routed drain hoses: Water may accumulate in the rear area of the sliding sunroof frame (see picture #1). For example, the rear drain hoses may have been routed without sufficient slope, which consequently leads to the drains overflowing. Water can enter the vehicle interior through the headliner. 2. Sliding sunroof adjustment: An improper positioning of the tilting/sliding roof within the roof frame may, under certain circumstances, lead to increased water ingress through the seal between the sliding sunroof frame and the roof. However, one drop is permissible here. 3. Material degradation: Over time, the seal of the tilting/sliding roof may experience age-related changes in its elasticity, which could potentially affect its watertightness. Remedy Test procedure for suspected water ingress via the sliding sunroof: • In all three possible cases, the headliner must be removed. • First, the complaint must be reviewed. A rain test should be performed for this purpose. If water enters through the sliding/tilting roof, compare the amount of water entering with the reference video in the appendix. Please note that due to its design, the sliding sunroof is not completely watertight. (see Video 3) • If the amount of water does not correspond to the expected normal condition, the three potential causes should be checked, insofar as they apply to the specific case. (see Video 2) Re. cause 1: • Route the left rear and right rear drain hoses of the sliding sunroof frame from the upper clip-on point to the lower clip-on point. • This must be carried out for both fastening points at the C-pillar and D-pillar. Carry out this step on both the left and right side of the vehicle. • Then move the water drain hoses of the roof luggage rack mounts from the lower clip-on point to the upper clipon point (see Pictures 2 and 3, Video 1). • Reinstall the roof lining. Re. cause 2: • Adjust the sliding sunroof frame position relative to the roof (height) in accordance with WIS document AR77.20- P-1100XG. Re. cause 3: • Replace the seal on the tilting/sliding roof (A2057800098). The vehicles affected are those with a production date up to 17.09.2025 and a chassis number up to W1N465.###.#X065180. If a vehicle still has a leakage in the sliding sunroof after this Clean point, please create a TIPS case.

The document

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Components

Body and frame

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