Service bulletin B520217

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10136728
Published by NHTSA	2018-05-14
Manufacturer's number	B520217
Manufacturer's date	2017-12-01
NHTSA component	SEATS

NHTSA's summary

SERVICE ACTION: CHECK PUMP FOR BACKREST WIDTH ADJUSTMENT: The backrest width adjustment and, the lumbar support adjustment of the front seats are accomplished by a common air pump.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Seats

Vehicles listed
BMW M3	2015, 2016, 2017
BMW M4	2015, 2016, 2017

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
B650414	2022-12-12. Service bulletin. According to the customer, the airbag warning light was on, but it may not be illuminated when the vehicle arrives in the workshop. 1. ACSM fault code "930A60 - Seat occupancy detection, front passenger; malfunction" is stored. The fault may or may not currently be present. Or 2. ACSM fault code "930A1C - Front passenger seat occupancy detection transmitting fault(moisture)" is stored. The fault may or may not currently be present.
B513316	2021-08-09. Service bulletin. Water sloshing noises coming from the rear passenger compartment (left or right) while driving Water ingress in the luggage compartment, or in the rear passenger compartment- rear seat bench rear passenger compartment foot well rear passenger compartment side panel Failure of various control units installed in the area of the water removal channel
B513316	2019-08-19. Service bulletin. LOSHING NOISES/WATER IN REAR PASSENGER COMPARTMENT: This Service Information bulletin replaces SI B51 33 16 dated August 2016.
B520919	2019-07-22. Service bulletin. CRACKING NOISE FROM SEAT BACKREST. Groaning/Cracking noises are heard from the front seat backrest when the vehicle is cornering.
B510815	2018-12-10. Service bulletin. Retrofit for Missing Rear Seat Through-Load Option. The rear seat through-load capability is 100% standard option for F83 (M4 Convertible) 2015 model year. Some vehicles may have this option is missing.
B520116	2018-12-10. Service bulletin. Front Seat Backrests Vibrates on Rough Roads. Both front seat backrests vibrate and rattle while driving over rough roads with the seat in an unloaded condition (no pressure applied on the backrest). Play at the inner backrest pivot point.
613414	2018-11-13. Service bulletin. Service Action: Replace Neck Warmer Control Unit. The control unit for the rear seat neck warmer may not be coded correctly. This causes the neck warmer to malfunction. Incorrect coding of the neck warmer control unit
613414	2018-11-13. Service bulletin. "?This Service Information bulletin supersedes SI B61 34 14 dated December 2014. PERFORM THE PROCEDURE OUTLINED IN THIS SERVICE INFORMATION ON ALL AFFECTED VEHICLES BEFORE CUSTOMER DELIVERY OR THE NEXT TIME THEY ARE IN THE SHOP FOR MAINTENANCE OR REPAIRS. designates changes to this revision SUBJECT Service Action: Replace Neck Warmer Control Unit. The control unit for the front seat neck warmers may not be coded correctly. This causes the neck warmer to malfunction. Incorrect coding of the neck warmer control unit AFFECTED VEHICLES This Service Action involves F33 and F83 vehicles produced to November 2014. First check if a Service Action label with a code number 724 is already attached to the B-pillar. If a code number 724 has been punched out, the Campaign has already been performed and no further action is necessary. Vehicles which require this Service Action will show it as ""Open"" when the VIN is checked in the ""Service Menu"" of DCSnet (Dealer Communication System) or when the key is read in the Key Reader."
B513416	2018-11-05. Service bulletin. RAISING OF WIND DEFLECTOR AT A HIGH SPEED. Unintentional lifting of the wind deflector occurs at a high speed and it is perceived that it may possibly detach. CAUSE Rear seat backrest not locked. This is not visually detectable at first glance. Make the customer aware of the proper rear seat engagement.
B513316	2018-11-05. Service bulletin. SLOSHING NOISES/WATER IN REAR PASSENGER COMPARTMENT. Water sloshing noises coming from the rear passenger compartment (left or right) while driving. Water ingress in the rear passenger compartment (rear seat bench / rear passenger compartment foot well / rear passenger compartment side panel) or luggage compartment. Failure of various control units installed in the area of the water removal channel. Poor water drainage due to dirt at the seal plug in the area of the fixed side glass/trim panel. Faulty clip on the water collecting channel. Dirt blocking the water drain to the side sill.