Airbag control unit with part number 9650393900

What does the airbag control unit 9650393900 do?

The airbag control unit 9650393900 forms the central control of the restraint system (SRS) of Peugeot. It evaluates the crash sensors and, in the event of an impact, decides within milliseconds whether airbags and seatbelt pretensioners are triggered.

At the same time, it continuously checks the system for faults. If it detects a fault, it shows this via the airbag warning light, so that the display reflects the condition of the vehicle.

After an accident, the unit stores crash data and locks itself. This lock applies to the control unit itself.

Why does the control unit 9650393900 fail?

Stored crash data after an accident is the most common cause, even if no airbag has deployed. Other causes include aged components, cold solder joints, moisture and corrosion in plug connectors, and voltage spikes.

A standard diagnostic tool cannot erase the crash data. The data remains in the control unit, which is exactly why a simple reset does not help.

The remaining causes relate to ageing and the environment. Electronic components lose performance over time, solder joints become brittle, and water or salt attack plug connectors. Voltage spikes from a weak battery or from jump-starting also stress the electronics.

How can you tell that the 9650393900 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. In addition, an error message appears, the diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared.

In this state, airbags and seatbelt pretensioners may not deploy in an emergency. You should therefore take this indication seriously.

Which cause lies behind it only becomes apparent when the fault memory is read out.

Which vehicles is the 9650393900 fitted in?

The 9650393900 was fitted by Peugeot in these vehicles: Peugeot 406 I (1995-2003) and I Facelift (1999-2005).

Below you will find the list of stored vehicles.

• Peugeot 406 I (1995-2003)
• Peugeot 406 I Facelift (1999-2005)

Comparing the part number on the label with this page only shows that it is the correct unit. Only the fault memory, which you should have read out before removal, clarifies the cause. Only then does it become clear whether the control unit is defective or whether a plug or cable is responsible.

For the same vehicles, we also repair control units with the part numbers 9630550780, 9638592580.

How does the repair of the 9650393900 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and remove the control unit 9650393900. Next, create a repair order online and send the unit in, well packed. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, erases the stored crash data and carries out a function test. Afterwards, your own unit is sent back 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.

How does the control unit 9650393900 get to Airbag24?

You send the control unit 9650393900 as a parcel or book a UPS collection for an extra charge. Airbag24 returns it by UPS after the repair.

The printed repair order goes in the parcel. Pack the unit shock-proof.