Airbag control unit with part number 5N0959655AD

What does the airbag control unit 5N0959655AD do?

The airbag control unit 5N0959655AD is the central control unit of the restraint system for Volkswagen. It reads the signals from the crash sensors, decides in an impact within fractions of a second which airbags and seatbelt pretensioners are triggered, and monitors the system continuously.

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

After an accident the unit stores crash data and locks itself. This procedure is fixed in the system.

Why does the control unit 5N0959655AD fail?

Most often the cause is crash data that remains in the unit after an accident, even if no airbag has deployed; a normal diagnostic tool cannot erase it. In addition there are ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or jump-starting.

Crash data in particular is worth a look in the fault memory before you suspect parts. The unit shows no external damage, so the entry is easily overlooked.

The other triggers vary: ageing and moisture act slowly, while voltage spikes occur suddenly.

How can you tell that the 5N0959655AD is defective?

The airbag warning light in the instrument cluster stays on continuously or intermittently, an error message appears in the instrument cluster, the diagnostic tool finds no connection to the control unit, or the fault memory cannot be cleared. Then the airbags and seatbelt pretensioners may not deploy in an emergency.

The light is one of the warnings you should keep in view on every journey. A display that stays on after switching on requires a check.

A diagnostic tool that cannot establish a connection also indicates a fault. The exact cause only emerges during readout and testing.

Which vehicles is the 5N0959655AD fitted in?

The 5N0959655AD is fitted in these vehicles: Volkswagen Tiguan 5N Facelift (2011-2018) and 5N (2007-2011).

The list shows the vehicles that Airbag24 assigns to this part number.

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

Comparing the part number on the label of the removed unit with this page only confirms that you have the right unit. Having the fault memory read out is a separate step and shows whether the control unit is defective or a plug or cable is the cause.

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 5N0959655AD work?

Have the fault memory read out first and attach the log. Then disconnect the battery, and only after that remove the control unit. Next create a repair order online and send it in well packed. At Airbag24, testing, repair and function test usually take 3–4 working days.

This sequence protects you from hazards during removal, so keep to it.

Airbag24 checks the unit on the test bench, repairs or replaces defective components and deletes stored crash data. Then a function test follows, and afterwards your own unit goes 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 5N0959655AD get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge, and after the repair Airbag24 returns it by UPS. The printed repair order goes into the parcel, and the unit is packed shockproof.

A sturdy box with ample padding protects the control unit better against shocks during transport.