# Service bulletin LI77.21\-P\-080504

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 11031557
- Published by NHTSA: 2026\-04\-25
- Manufacturer's number: LI77.21\-P\-080504
- Manufacturer's date: 2026\-04\-24
- NHTSA component: VISIBILITY/WIPER

## NHTSA's summary

Complaint The panoramic sliding sunroof operates in a stepped movement. The panoramic roof becomes denormalized without an apparent reason \(not directly after control unit replacement\). Automatic operation of the glass panel and roller sunblind is not possible; only tip‑mode operation is available. Cause Resetting the panoramic roof control unit \(PSD, A98, N70/1, TSSR223\) can lead to loss of normalization. The root cause for the control unit reset is currently under investigation. Remedy Contribution to cause analysis: • Print the attached document “Panoramic Roof Customer Questionnaire.” • Complete the questionnaire together with the customer. • Open a TIPS case and attach the completed questionnaire. • Submit the TIPS case to the Body / Chassis / Entertainment inbox. Repair: Perform Initial Start‑Up of the panoramic roof control unit \(PSD, A98, N70/1, TSSR223\).

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031557-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031557-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Glass, wipers and mirrors, Wipers and washers

## Vehicles listed

- 2024 to 2026 MERCEDES\-BENZ E 450 4MATIC ALL\-TERRAIN
- 2026 MERCEDES\-BENZ E53 E 4MATIC\+ ALL\-TERRAIN

JSON: [/v1/bulletins/11031557](/v1/bulletins/11031557)

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