Information concerning all Mercedes models​


Our experience show that just disconnecting and reconnecting correctly working seat occupancy sensor, even if there are no fault codes in the airbag control unit, can cause changes in the airbag control unit.

The changes may be different:

unlocked airbag control unit

[In Star Diagnosis: Restraint system control unit: Control unit version – parameter “Initial startup of control unit”, value – “Not performed”]


– changed coding

– others


The result can be:

  • flashing SRS warning (unlocked control unit)
  • fault code in the airbag control unit – wrong coding of the seat occupancy sensor
  • maybe other changes that we haven’t come across


1. Flashing SRS warning light

– lock the airbag control unit by the procedure of INITIAL STARTUP or a proper actuation.

Attention! In case when an emulator is installed in the car, the initial startup procedure may not be possible to be performed – during the procedure the airbag control unit must check 2 occupancy levels of the seat – empty and occupied seat. The emulator shows only occupied seat. In such situation only adequate actuation remains – a good mechanic specialized in Mercedes should cope. We do not do such things by phone or e-mail.

Click on the picture to enlarge

Below we’re showing you how to lock the control unit in DAS, XENTRY, VEDIAMO and DTS Monaco.





2. Changed coding – change seat occupancy sensor setting in the airbag control unit.

3. Another solution adequate to the problem being faced.

The above steps can be performed using Star Diagnosis.

Photos taken courtesy of a friendly workshop specializing in Mercedes repairs.