Check the 3-point automatic-reel belt (530i 2017-2022, 530i xDrive 2017-2022, 530e PHEV 2018-2022, 530e xDrive PHEV 2018-2022, 540i 2017-2022, 540i xDrive 2017-2022, M550i xDrive 2018-2022)
General considerations when checking seat belts:
- After replacing the EMA/REMA* automatic reel
* EMA = electromotive automatic (seat belt) reel
*REMA = reversible electromotive reel
Check the additional functions for function when replacing the EMA/REMA automatic reel after PROGRAMING/ENCODING the vehicle.
For the EMA/REMA automatic reel functional check, it is sufficient to check that the belt slack* has been eliminated.
* Belt slack is seat belt play when the seat belt is fastened. When the seat belt is fastened, it does not immediately lie taut against the body.
Check if belt slack was eliminated for EMA to 07/12:
- Get in, close the doors and latch the left seat belt buckle contact
- EMA eliminates belt slack
If belt slack was not eliminated, the procedure described below must be followed:
- Allow vehicle to assume complete sleep mode and repeat the functional check.
- All doors must be closed!
- EMA, left, must be installed and connected correctly.
- Work through all fault code entries before the repeating the functional check
Check if belt slack was eliminated for REMA from 07/12 onwards:
- Lock left seat belt buckle contact and perform function check with diagnosis system using to an appropriate scan tool.
- Alternatively, take a test drive at a speed of > 10 km/h
The automatic reel is completely maintenance-free and must not be opened.
- After an accident
The seat belts must be checked after an accident.
At the beginning of the check, attempt to obtain information about the occupation of the seats in the vehicle that was involved in an accident. If this is not possible, check all of the seat belts in the vehicle and replace them if necessary.
In the event of deformations on the vehicle, you must subject the components of the restraint system affected in this area such as e.g.
- Seat belt
- Anchor fitting tensioner
- Seat belt height adjustment
- Seat belt tensioner
- Impact sensor
- Etc.
To a function check and a visual inspection.
If you are in any doubt as to the unimpaired operability of restraint system components, these components must be replaced in the interests of safety!
If a seat belt has to be replaced following an accident (e.g. in the event of a frontal and/or oblique collision with permanently deformed impact absorbers/deformation elements or cross-members), the complete seat belt must be replaced! The complete seat belt comprises:
- Upper seat belt
- Lower strap
- Anchor fitting tensioner
- Seat belt buckle (belt tensioner)
- Seat belt height adjustment
- Mounting bolts of all components
The following must also be checked and replaced, if applicable:
- Belt coding on the body
- Belt coding on the seat
- Seat rails.
- Seat structure (frame, etc.)
Alignment tests on the seat and the seat rails are not permitted!
The following explanations and the CHECK LIST for the 3-point automatic-reel seat belt may be helpful.
An unusable seat belt or a seat belt worn in a serious accident should be destroyed immediately after removal to guarantee that it can not be used again.
Check the automatic reel and seat belt strap :
The automatic reel has two independent activation systems for seat-belt locking.
The first activation system locks the automatic reel when driving quickly around curves, driving in tight curves, on extreme inclinations (vehicle rolls over) and during sharp braking or crash.
To check, the backrest must be placed in the upright position and both hands held in a supporting position close to the steering wheel. The brakes are then operated with full intensity while driving on a dry roadway and at double walking speed.
The seat belt must lock.
The second activation system provides additional safety and is controlled by inertia mass.
If the reel locks when the seat belt strap is pulled out suddenly, this system is also OK.
In addition, the automatic reel (EMA/REMA) must eliminate belt slack.
Check whether an attempt was made to eliminate belt slack:
- Get in, close the doors and latch the left seat belt buckle contact
- EMA/REMA eliminates belt slack
If belt slack was not eliminated, the procedure described below must be followed:
- Allow vehicle to assume complete sleep mode and repeat the functional check.
- All doors must be closed!
- EM/REMALI must be installed and connected correctly
- Work through all fault entries before the functional check is carried out again.
Replace the faulty or activated automatic reel.
The automatic reel is completely maintenance-free and must not be opened.
Precondition for complete, problem-free retraction of seat belt straps:
- The seat belt straps must not be twisted!
- The seat belt straps must not be damaged!
When placed to one side, the seat belt straps of the front seats must retract fully.
With the seat belt straps in the seat bench, a small remaining loop in the seat belt strap is acceptable due to increased friction between the seat belt strap and the seat bench cover if:
- This remaining loop is fully retracted when the seat belt strap is re-guided.
The seat belt strap should only be cleaned with a lukewarm soap solution or a commercial mild detergent.
Seat belt strap must never be cleaned chemically or dyed.
The automatic reel and seat belt strap must be replaced in the event of:
- Creasing
- Unraveling
- Pinches
- Cracks and tears
- Traces of melting
- Traces of wear on the coating of the buckle tongue or on the seat belt guide loop.
Check the lower strap (belt tensioner):
To fasten a seat belt, the buckle tongue should insert easily and engage in the seat belt buckle with an audible click.
When the "Red button" is pressed, the buckle tongue must be ejected from the seat belt buckle under spring pressure.
If the seat belt buckle cover is missing or damaged, the lower strap must be replaced.
Replace the activated belt tensioner including the complete seat belt with seat belt height adjustment and mounting bolts and check the
- Belt coding on the body
- Belt coding on the seat
- Seat rails.
- Seat structure
Criteria for an activated mechanical belt tensioner:
- Very low position of seat belt buckle (comparisons with new part).
Criteria for an activated pyrotechnic belt tensioner:
- Very low position of seat belt buckle (comparisons with new part).
- Airbag indicator light permanently lit: read out airbag system fault memory.
The belt tensioners can be activated under certain circumstances even when the seat is not occupied. If it is definite that the seat belt system was not used (seat was not occupied), there is no need to replace the following components after a check.
- Upper seat belt
- Add-on parts (seat belt height adjustment, screws)
- Belt coding on the body
- Belt coding on the seat
- Seat rails.
Checking end fitting pretensioner:
Replace the triggered end fitting pretensioner including the complete seat belt with seat belt height adjustment, lower strap and mounting bolts and check the
- Belt coding on the body
- Belt coding on the seat
- Seat rails.
- Seat structure
Criteria for a triggered end fitting pretensioner:
- A triggered end fitting pretensioner can be recognized from the wrapped seat belt strap around the shaft.
- Airbag indicator light permanently lit: read out airbag system fault memory.