Airbag control unit with part number 5N0959655B

What does the airbag control unit 5N0959655B do?

The airbag control unit 5N0959655B is the central control unit of the restraint system (SRS) in Volkswagen. It evaluates the crash sensors, decides within milliseconds in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. An accident leaves crash data in the memory, after which the unit locks itself.

If it detects a fault, it reports it via the airbag warning light in the instrument cluster.

Decisions taking place within milliseconds require constant self-monitoring. The unit therefore checks its surroundings continuously during operation.

Why does the control unit 5N0959655B fail?

The most common cause is crash data that remains in the memory after an accident, even if no airbag was triggered; a normal diagnostic tool does not erase it. Other causes are aged components, cold solder joints, corrosion on plug connectors and voltage spikes.

The entries are created by the incident itself and remain even without triggering.

Aged components and cold solder joints act gradually. Moisture and corrosion on plugs worsen the contact over time.

Voltage spikes, for example from a weak battery or a jump start, hit the electronics directly. Which cause applies is only determined by the investigation on the test bench.

How can you tell that the 5N0959655B is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, an error message is displayed, the diagnostic tool finds no control unit, or the fault memory remains. In that case airbags and seatbelt pretensioners may not be able to trigger in an emergency.

Respond to the warning light promptly by having the fault memory read out.

If the diagnostic tool cannot connect to the control unit, there is a fault in communication. It may lie in the control unit itself or in the wiring between.

A fault memory that cannot be cleared remains as a notice in the system.

Which vehicles is the 5N0959655B fitted in?

Compare your vehicle with the list. For Volkswagen, the control unit 5N0959655B is fitted in these vehicles: Volkswagen Tiguan 5N Facelift (2011-2018) and 5N (2007-2011).

The models for which we have data are shown in this list:

• Volkswagen Tiguan 5N Facelift (2011-2018)
• Volkswagen Tiguan 5N (2007-2011)

Two things help you decide. Matching the part number on the label with this page ensures that you have the right unit. The result of the fault memory read-out, by contrast, shows whether the control unit itself is defective or whether a plug or cable is behind it.

For the same vehicles, we also repair control units with the part numbers 5N0 959 655 AA, 5N0 959 655 AB 005, 5N0 959 655 AE, 5N0 959 655 J, 5N0 959 655 Q, 5N0 959 655 R.

How does the repair of the 5N0959655B work?

First have the fault memory read out, disconnect the battery and then remove the control unit 5N0959655B. Processing at Airbag24 usually takes 3–4 working days, after which your unit is returned.

Create the repair order online; enclose the fault memory log and pack the unit well before sending it.

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

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 5N0959655B get to Airbag24?

The control unit 5N0959655B goes to Airbag24 as a parcel, or you book a UPS collection for an extra charge. UPS handles the return after the repair.

Put the printed repair order into the parcel with the unit and pad it so that it is shock-proof.