BMW 1999-2005 M3 Service Manual page 1192

Seat Belts
Problem
Seat belt does not retract
automatically. (See note.)
Automatic belt squeaks when
belt fastened or unfastened.
Seat belt pyrotechnic
tensioner triggered
Convertible models only:
Front seat back requires
excessive force to lock or
unlock
Seat back lock warning lamp
on when seat back is locked;
or warning lamp lights up
when seat back is shaken
Contact surface of inertia reel
warped
Seat back warped or
deformed
Head restraint carrier not
parallel
Seat movement sticky or
sluggish at some point in its
range; unusual noises
Front seat shows evidence of
contact with body structural
part (e.g., door)
Front seat shows evidence of
contact with external objects
4 of 5
http://ebahn.bentleypublishers.com/BMW/3/E46/Repair%20Manuals/7...
Probable cause
Automatic reel loose
Return spring broken inside
reel
Excessive friction in belt
guides
Automatic reel loose
Return spring broken inside
reel
Accident triggered
pyrotechnic deployment
Accident damage to seat via
seat belt
Seat back lock microswitch
defective
Microswitch electrical harness
connectors loose or defective
Seat back lock is damaged
Accident damage
Accident damage
Accident damage
Accident damage (side)
Accident damage (side)
Accident damage (rollover)
Repairs
Tighten reel mounting bolt.
Replace reel assembly.
Replace reel assembly.
Tighten reel mounting bolt.
Replace reel assembly.
Replace complete automatic
seat belt. Also check
retaining bracket of belt
tensioner for twist.
Replace front seat.
Replace microswitch
Repair electrical leads.
If fault persists, replace front
seat.
Replace front seat.
2/25/2009 11:20 PM