# Service bulletin B540121

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: 10194303
- Published by NHTSA: 2021\-05\-24
- Manufacturer's number: B540121
- Manufacturer's date: 2021\-04\-01
- NHTSA component: EQUIPMENT; VISIBILITY:SUN/MOON ROOF ASSEMBLY

## NHTSA's summary

SUNROOF REVERSES WHEN CLOSING: After the vehicle is left in the hot sun and/or high temperatures with the sunroof in the vented position, the sunroof may reverse \(anti\-trap activates\) when closing.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2021/MC-10194303-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2021/MC-10194303-9999.pdf)

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

## Components

Equipment and accessories, Glass, wipers and mirrors, Sunroof

## Vehicles listed

- 2017 to 2019 BMW 740E
- 2017 to 2021 BMW 740I
- 2016 to 2017 BMW 740LI
- 2020 BMW 745E
- 2018 to 2019 BMW 750I
- 2016 to 2019 BMW 750LI
- 2021 BMW 750LI
- 2018 to 2021 BMW B7 ALPINA
- 2021 BMW F 850 GS ADVENTURE
- 2017 to 2021 BMW M760I

## Other bulletins for the same vehicles and component

- [B540521](/bulletins/10242698.md), 2023-09-25, Service bulletin: STRUCTURE:BODY:ROOF AND PILLARS; VISIBILITY:SUN/MOON ROOF ASSEMBLY. ?The sunroof will not operate in either direction.
- [B540521](/bulletins/10228433.md), 2023-01-03, Service bulletin: VISIBILITY:SUN/MOON ROOF ASSEMBLY. The sunroof will not operate in either direction. There are NO faults stored related to the sunroof. If the vehicle has any faults stored related to the sunroof, this bulletin does not apply.
- [B540319](/bulletins/10160345.md), 2019-05-20, Service bulletin: EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; VISIBILITY:SUN/MOON ROOF ASSEMBLY. GROANING NOISE FROM SUNROOF . A groaning noise is present from the area between the front and rear sunroof glass panels only with the sunroof completely closed. Venting the front sunroof glass causes the noise to stop. The front sunroof glass is rubbing against the rubber seal of the rear sunroof glass.
- [B540319](/bulletins/10160262.md), 2019-05-20, Service bulletin: VISIBILITY:SUN/MOON ROOF ASSEMBLY. GROANING NOISE FROM SUNROOF . A groaning noise is present from the area between the front and rear sunroof glass panels only with the sunroof completely closed. Venting the front sunroof glass causes the noise to stop. The front sunroof glass is rubbing against the rubber seal of the rear sunroof glass.
- [B540718](/bulletins/10154854.md), 2019-03-18, Service bulletin: VISIBILITY:SUN/MOON ROOF ASSEMBLY. PANORAMIC SUNROOF DOES NOT OPEN OR CLOSE. The panoramic sunroof will not open or close. The sunroof may only tilt with no other functions available. There are no faults stored for the panoramic sunroof. A software error in the Roof Function Center \(FZD\).
- [B540718](/bulletins/10153641.md), 2019-02-25, Service bulletin: VISIBILITY:SUN/MOON ROOF ASSEMBLY. PANORAMIC SUNROOF DOES NOT OPEN OR CLOSE. The panoramic sunroof will not open or close. The sunroof may only tilt with no other functions available. There are no faults stored for the panoramic sunroof. A software error in the Roof Function Center \(FZD\).

JSON: [/v1/bulletins/10194303](/v1/bulletins/10194303)

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