Airbag control unit with part number 65.77-6920848

What does the airbag control unit 65.77-6920848 do?

As the central control unit of the restraint system (SRS) of BMW, the airbag control unit 65.77-6920848 is responsible. It evaluates the signals from the crash sensors, decides within milliseconds in a crash which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. After an accident it stores crash data and locks itself.

The unit shows faults via the airbag warning light in the instrument cluster. The evaluation runs in the background, and you do not have to operate anything.

Why does the control unit 65.77-6920848 fail?

The most common cause is crash data stored after an accident, even without airbag deployment. On this control unit, deleting the crash data is often not possible; if you would like it deleted, contact Airbag24 briefly before sending the unit in, and Airbag24 will then check the number. Other causes are aged electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

Stored crash data arises after an accident, even if no airbag has deployed, and it remains in the unit. That explains why the warning stays on.

Repairing a fault on this control unit is normally still possible, regardless of whether the crash data can be deleted. Aged electronic components, cold solder joints, moisture and corrosion at plug connectors or voltage spikes, for example from a weak battery or a jump start, are also possible causes.

How can you tell that the 65.77-6920848 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. In addition there may be an error message in the instrument cluster, a diagnostic tool with no connection to the control unit, or a fault memory that cannot be cleared. In that case airbags and seatbelt pretensioners may possibly not trigger in an emergency.

The warning light is the most noticeable sign, and it reports a fault that the control unit has detected. Whether it lights up permanently or only intermittently does not change its meaning.

If the diagnostic tool cannot establish a connection, the control unit cannot be tested. Further testing is then unavoidable.

Which vehicles is the 65.77-6920848 fitted in?

The airbag control unit 65.77-6920848 is fitted in these vehicles: BMW M5 E39 (1998-2003); BMW 5 Series E39 (1995-2004).

The following assignment exists for this part number:

• BMW M5 E39 (1998-2003)
• BMW 5 Series E39 (1995-2004)

Comparing the part number on the unit with this page ensures that it is the matching unit. Whether the control unit itself is defective or a plug or cable is the cause only becomes clear from the fault memory, so have it read out before removal.

For the same vehicles, we also repair control units with the part numbers 65 77 6 919 781, 65 77 6 919 789, 65.77-6900727, 6577-6997257, 6577-8372521, 6577-8374799.

How does the repair of the 65.77-6920848 work?

First have the fault memory read out and attach the log. Then disconnect the battery and only then remove the control unit. Next, create a repair order online and send the unit in well packed.

At Airbag24 the unit is checked on the test bench, defective components are repaired, and a function test follows. As a rule these steps take 3–4 working days, after which your own unit is returned.

If you would like the crash data deleted, contact Airbag24 briefly before sending the unit in.

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.

How does the control unit 65.77-6920848 get to Airbag24?

You send the unit as a parcel, or you book a UPS collection for an extra charge. After the repair Airbag24 returns it by UPS.

The printed repair order goes into the parcel. Pack the unit shock-resistant.