Airbag control unit with part number 65.77-6949899

What does the airbag control unit 65.77-6949899 do?

The 65.77-6949899 is an airbag control unit for BMW and forms the central control unit of the restraint system (SRS). In an accident it decides within milliseconds, based on the crash sensors, which airbags and seatbelt pretensioners are deployed; during normal operation it monitors the system constantly.

If the unit detects a fault, it indicates it via the airbag warning light. From the outside it is a flat, wide box. The label reads “SGM” or “SIM” and “LEAR”.

For this design we repair only fault 93F9 (voltage reserve or energy reserve); we cannot fix other faults on this unit.

Why does the control unit 65.77-6949899 fail?

Fault 93F9 concerns the voltage reserve or energy reserve of the control unit 65.77-6949899. In general, aged electronic components, cold solder joints, moisture and corrosion, or voltage spikes can damage the electronics of a control unit.

Only the test on the test bench reveals which cause applies to your unit. A prerequisite for the repair is that the fault memory contains fault 93F9.

Regarding the crash data: with this design it is not located in the control unit but in another module of the airbag system. If you would like to have crash data deleted, please get in touch with us beforehand and we will clarify what is possible.

How can you tell that the 65.77-6949899 is defective?

You recognise the defect by the airbag warning light, which lights up permanently or intermittently in the instrument cluster, and by fault 93F9 (voltage reserve or energy reserve) in the fault memory. As long as the defect exists, airbags and seatbelt pretensioners may fail to deploy in an emergency.

In addition, a message about the restraint system may appear in the instrument cluster.

The warning light alone does not say which fault is present. Only reading out the fault memory shows it, and only with 93F9 can we repair this unit.

Which vehicles is the 65.77-6949899 fitted in?

The airbag control unit 65.77-6949899 is fitted in these vehicles: BMW 7 Series E65 and E66 L.

The vehicles are listed individually:

• BMW 7 Series E65
• BMW 7 Series E66 L

Check two things before sending it in. First: does the part number on the label of the removed unit match this page? That only clarifies whether it is the right unit. Second: what does the fault memory say? Reading it out shows whether the control unit is defective or a plug or cable is the cause, and whether 93F9 is entered.

For the same vehicles, we also repair control units of this design with the part numbers 65776920483, 65776950242, 65776967658, 65776949906, 65776922144, SI692214401F.

How does the repair of the 65.77-6949899 work?

You first read out the fault memory and enclose the log, then disconnect the battery and only then remove the control unit. Afterwards you create a repair order online and send in the well-packed unit; the log must show fault 93F9.

Airbag24 checks the unit on the test bench, replaces defective components and carries out a function test.

Processing at Airbag24 generally takes 3–4 working days. After that, your own unit is returned to you. Our repairs come with 2 years' statutory liability for defects. The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.

If you would like to have crash data deleted, please get in touch with us before you create the repair order.

How does the control unit 65.77-6949899 get to Airbag24?

Send the unit in yourself as a parcel or have UPS collect it for an extra charge; the return shipment after the repair is likewise handled by UPS.

Pack the control unit so that it is protected against impacts and enclose the printed repair order.