B520121 Service Bulletin/Repair Instructions

3/2/2021
52 01 21_SEAT FAILS TO INITIALIZE DUE TO MISSING END STOP
SIB 52 01 21

SEAT FAILS TO INITIALIZE DUE TO MISSING END STOP
2021-02-05
MODEL

E-Series

F33

F44

F90

F95

F96

G05

G06

G07

G12

G30

G32
Model Description

4 Series Convertible

2 Series Gran Coupe

M5 Sedan

X5 M Sports Activity Vehicle

X6 M Sports Activity Coupe

X5 Sports Activity Vehicle

X6 Sports Activity Coupe

X7 Sports Activity Vehicle

7 Series Sedan

5 Series Sedan

640i xDrive Gran Turismo
SITUATION

Front seat will not calibrate/initialize, and the stored faults cannot be deleted:

802BCA - Driver seat FAS: Seat position not sent due to missing or invalid calibration

8029CA - Passenger seat BFS: Seat position not sent due to missing or invalid calibration
CAUSE

These faults can set if the factory-installed end stop (spacer) is removed from the seat rail assembly. On

some BMW models this end stop is installed to limit the movement of the seat assembly. This ensures that

occupants receive maximum protection from the air bag system.

These end stops may not have been transferred over from the original rails during seat rail replacement.

Replacement parts may not contain these model-specific end stops.

A customer may have removed these stops to try and get the seat to move further rearward
Once these end stops have been removed, the seat motor will attempt to move the seat beyond the

programmed limit in the seat module. Once the hall sensor reading moves outside of the design window,

and the seat is no longer in a position to protect the occupant in an accident, the seat module will not

initialize.
CORRECTION

1. If this occurs after seat rail replacement, and the new rail does not include the end stop, then swap the end stop

from the original rail.

2. If this occurs after a customer has removed the end stop:

Request the customer supply the end stops for reinstallation if still available

Order end stop if available separately in ETK, see Parts section below.

If the end stop is not available separately in ETK then

it may only come with an entire seat rail assembly.

contact Parts Technical Support via a TTS TSARA case for support
INFORMATION

F90 G12 G30 spacer

(arrow).
Copyright ©2021 BMW of North America, Inc.

1/4
3/2/2021
52 01 21_SEAT FAILS TO INITIALIZE DUE TO MISSING END STOP
F95 F96 G05 G06 G07

spacer.

Top photo shows end

stop (spacer) installed,

lower photo shows rail

minus the spacer.
Copyright ©2021 BMW of North America, Inc.

2/4
3/2/2021
52 01 21_SEAT FAILS TO INITIALIZE DUE TO MISSING END STOP
F44 spacer.

Top photo shows end

stop (spacer) installed,

lower photo shows rail

minus the spacer.
If there are other models or end stops not pictured that you want to have added to this bulletin, please

submit an INFO ONLY TSARA case.
PARTS INFORMATION

Obtain and confirm the part numbers for your specific vehicle by entering the chassis number in either ETK

or AIR which takes into account specific equipment and/or options.

Part Number

52 10 7 382 009
Description

SPACER seat Rail End Stop F90 G12 G30
Quantity

2 per seat
Copyright ©2021 BMW of North America, Inc.

3/4
3/2/2021
52 10 7 469 879
52 01 21_SEAT FAILS TO INITIALIZE DUE TO MISSING END STOP
SPACER seat Rail End Stop F95 F96 G05

G06 G07
2 per seat
WARRANTY INFORMATION

For information only.
QUESTIONS REGARDING THIS BULLETIN

Technical inquiries

Warranty inquiries

Parts inquiries
Submit feedback at the top of this bulletin

Submit an IDS ticket to the Warranty Department or use

the chat available in the Warranty Documentation Portal

Submit an IDS ticket to the Parts Department
Copyright ©2021 BMW of North America, Inc.

4/4

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