Restraints - Safety Belt Extender 'Handover' Concerns
SI B72 01 11
Safety Belts and Accessories (Body)
August 2011
Technical Service
This Service Information bulletin replaces the following SIs: B72 28 06, B72 03 07, B72 05 07, B72 01 08 and B72 03 10.
SUBJECT
Safety Belt Extender "Handover" Fails to Deliver the Belt to the Customer
MODEL
E92 (3 Series Coupe)
SITUATION
The customer states that the seat belt extender "handover" on the front driver's or passenger side failed to deliver the belt. One or more of the
following situations may apply:
^ The safety belt extender extends but the belt slips off.
^ The "hand" on the extender fails.
^ The safety belt is twisted.
^ The extender will not operate and makes noise while extending.
CAUSES
One or more of the following causes may apply:
1. The safety belt is incorrectly positioned.
2. The "hand" on the extender has mechanically failed.
3. The safety belt slips off the "hand" due to excessive resistance from the seat belt reel, not allowing the belt to extend properly. The seat belt is
twisted.
4. The safety belt slips off the "hand" due to the belt material being excessively worn.
5. The safety belt extender fails to extend or retract intermittently due to FRM (Footwell Module) software.
6. The safety belt extender is noisy or inoperative, due to a communication problem or incorrect power or ground.
CORRECTION
For a complete overview of the safety belt extender system, please review ISTA (Integrated Service Technical Application) document
"FUB-FUB-FB-520001-K06 Seat belt extender".
Follow the correction information for the applicable cause listed above:
1. The safety belt is incorrectly positioned:
Check to make sure the "clamping bushes" are installed on both sides on the lower belt slide rail. Install the "clamping bushes" if necessary.
Refer to ISTA Repair Instructions REP 7211080 - Removing and installing/replacing left or right seat-belt extender "hand". Use the only
information is provided on how to install the "clamping bushes".
2. The "hand" on the extender mechanically fails to catch the safety belt:
Check/install the "clamping bushes" as required (Step 1). Inspect the "hand" for a mechanical malfunction (loss of spring tension) on the
affected side (refer to Repair Hints in attachment to this Service Information bulletin). For the replacement of the "hand" on the left or right
side, refer to the attachment to this Service Information bulletin based on the vehicle's production date.
Note:
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 139
Do not use ISTA Repair Instructions REP 72 11 080 for replacing the "hand" until further notice.
3. The safety belt slips over the "hand" due to slow retraction, twisting, or doubling over:
Inspect the safety belt for slow retracting and make sure it is not twisted or doubled over (refer to Repair Hints in the attachment to this
Service Information bulletin).
4. The seat belt slips off the "hand" due to the belt material being excessively worn:
Inspect the safety belt material for any wear or damage. Replace the safety belt as needed.
5. The safety belt extender fails to extend or retract intermittently, due to an FRM software error (only affects vehicles up to March 2007
production):
Check the current I-level in the vehicle, and if it is lower than E89-07 03 510, the software must be updated. Start a new programming session
and check in the measure plan if the FRM is not in the control units list. Then select the FRM control unit for software update and coding.
Complete the session and recheck function and operation. For information about ISTA/P, refer to CenterNet/Aftersales/Aftersales Business
Development & Marketing Portal/Service Operations Programming.
6. The safety belt extender is noisy or inoperative, due to a communication error or incorrect power and ground:
Perform a vehicle test using ISTA. Troubleshoot any FRM faults related to the safety belt extender. Follow the test plan and make sure the
power, ground, and LIN BUS reading values are within the nominal value for operation (refer to the wiring diagram). Please submit Diagnosis
feedback from ISTA to report any test plan errors or any unclear or misleading diagnosis recommendations. Submit a PuMA case if you need
further assistance.
PARTS INFORMATION
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 140
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 141
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 142
WARRANTY INFORMATION
ATTACHMENT
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 143
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 144
2010 BMW 335i Coupe (E92) L6-3.0L Turbo (N54) Page 145
