# Service bulletin B520121

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: 10188945
- Published by NHTSA: 2021\-03\-15
- Manufacturer's number: B520121
- Manufacturer's date: 2021\-02\-01
- NHTSA component: SEATS

## NHTSA's summary

SEAT FAILS TO INITIALIZE DUE TO MISSING END STOP: Front seat will not calibrate/initialize.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2021/MC-10188945-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2021/MC-10188945-9999.pdf)

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

## Components

Seats

## Vehicles listed

- 2020 to 2021 BMW 228I
- 2014 to 2016 BMW 428I
- 2017 to 2020 BMW 430I
- 2014 to 2016 BMW 435I
- 2017 to 2020 BMW 440I
- 2018 to 2021 BMW 530E
- 2017 to 2021 BMW 530I
- 2018 to 2019 BMW 540D
- 2020 BMW 540D
- 2017 to 2021 BMW 540I
- 2018 to 2019 BMW 640I
- 2020 BMW 640I
- 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
- 2018 BMW C 400 X
- 2021 BMW F 850 GS ADVENTURE
- 2017 BMW F800 R
- 2020 to 2021 BMW M235I
- 2018 to 2021 BMW M5
- 2017 BMW M550I
- 2018 to 2021 BMW M550I
- 2017 to 2021 BMW M760I
- 2018 BMW R NINE T SCRAMBLER
- 2017 BMW R1200 RT POLICE
- 2019 to 2021 BMW X5
- 2020 to 2021 BMW X6
- 2020 BMW X6 M
- 2019 to 2021 BMW X7

## Recalls for the same vehicles and component

- [2022501](/recalls/tc/2022501.md), 2022-09-07: Seats And Restraints
- [22V670000](/recalls/nhtsa/22V670000.md), 2022-09-07: SEATS
- [21V156000](/recalls/nhtsa/21V156000.md), 2021-03-10: SEATS:MID/REAR ASSEMBLY:HEAD RESTRAINT
- [19V135000](/recalls/nhtsa/19V135000.md), 2019-02-27: SEATS
- [2019070](/recalls/tc/2019070.md), 2019-02-14: Seats And Restraints
- [19V096000](/recalls/nhtsa/19V096000.md), 2019-02-13: SEAT BELTS; SEATS

## Other bulletins for the same vehicles and component

- [B720125](/bulletins/11028928.md), 2026-02-23, Warranty extension: AIR BAGS; ELECTRICAL SYSTEM; SEATS. A situation may occur where the front passenger seat is not occupied; however, a “fasten seat belt” warning and a front passenger seat air bag deactivation message appears. If the situation is currently present, sit in the seat and move the seat to a slightly different position. The POL \(Passenger Occupancy Light\) light should now function correctly. In some cases, the Air bag Warning Light was illuminated, and the following Advanced Crash Safety Module \(ACSM\) fault is stored: 930A1C \- Front passenger seat occupancy detection transmitting fault \(moisture\)
- [B520920](/bulletins/11012089.md), 2024-12-31, Service bulletin: SEATS. HEAD RESTRAINT AND/OR BACKREST OF 3RD ROW SEATS CANNOT BE FOLDED DOWN
- [B520524](/bulletins/11006735.md), 2024-09-01, Service bulletin: SEATS. A rattling noise can be heard emanating from the area of the rear seat backrest of the second row ofseats. The noise does not occur when the rear seat backrest is folded down.
- [B521019](/bulletins/10252279.md), 2024-04-01, Service bulletin: SEATS. The seat leather upholstery detaches from the front of the thigh support \(aka knee bolster\) of either front seat.
- [B521723](/bulletins/10249023.md), 2024-02-01, Service bulletin: ELECTRICAL SYSTEM; SEATS. Customer states one of the front seats is inoperative. The seat heater and power supply are inoperative. During the vehicle test, the seat module does not respond. The power supply fuse for the seat module isfound to have blown.
- [B522319](/bulletins/10246302.md), 2023-12-06, Service bulletin: SEATS. Two areas of the third\-row seat backrest that may cause a noise concern have been added.
- [B522319](/bulletins/10244258.md), 2023-11-01, Service bulletin: SEATS. Second seat row blocking access to third seat row, program seat modules. Visible stitching on first row sport seat. Third seat row backrest Bowden cable routing and length change.
- [B520920](/bulletins/10244257.md), 2023-11-01, Service bulletin: SEATS. Various concerns about the third row of seats: 1. Head restraint \(aka headrest\), on one or both sides, cannot be folded down. 2. Third\-row seating, on one or both sides, cannot be folded down.
- [B520920](/bulletins/10242695.md), 2023-09-25, Service bulletin: SEATS. ?Various concerns about the third row of seats.
- [B520121](/bulletins/10242694.md), 2023-09-25, Service bulletin: SEATS. ?The front seat will not calibrate/initialize, and the stored faults cannot be deleted.

JSON: [/v1/bulletins/10188945](/v1/bulletins/10188945)

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