Airbag control unit with part number 5C0959655J

What does the airbag control unit 5C0959655J do?

The airbag control unit 5C0959655J is the central control unit of the restraint system (SRS) for Volkswagen. It monitors the crash sensors continuously and decides in a split second during an accident which airbags and seatbelt pretensioners to trigger. It shows faults via the airbag warning light.

After an accident the unit stores crash data and then locks itself.

The sensors, wiring harnesses and airbags form the restraint system together with the control unit. If one link fails, the function of the overall system may be limited.

Why does the control unit 5C0959655J fail?

Stored crash data is the most common cause, even if no airbag was deployed in the accident. A normal diagnostic tool does not make it disappear. Other possible causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes from a weak battery or a jump start.

The crash data is created in the control unit itself as soon as it evaluates the accident, and remains in memory afterwards.

Over time electronic components age, and moisture can attack plug connections until they corrode. Voltage spikes when starting the engine or during a jump start put additional strain on the unit.

How can you tell that the 5C0959655J is defective?

The airbag warning light in the instrument cluster stays on permanently or lights up from time to time, and a fault message may appear there. The diagnostic tool gets no connection to the control unit, and the fault memory cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may fail to deploy in the event of a defect, so every warning light indication deserves attention.

The warning light shows the defect immediately. If you take this indication seriously, have the unit examined promptly.

Which vehicles is the 5C0959655J fitted in?

The 5C0959655J is fitted in these vehicles: Volkswagen Jetta 6 (2010-2018).

The vehicles this part number is recorded for are listed here.

• Volkswagen Jetta 6 (2010-2018)

First check whether the part number on the label of the removed unit matches this page. This only confirms that it is the correct unit, not the cause. Therefore have the fault memory read out beforehand, because only it shows whether the control unit is defective or a plug or cable is behind the fault.

For the same vehicles, we also repair control units with the part numbers 5C0 959 655C, 5C0959655E, 5C0959655F, 5N0 959 655 AC 702.

How does the repair of the 5C0959655J work?

First have the fault memory read out and enclose the log with the unit. Then disconnect the battery and only afterwards remove the control unit. Create the repair order online and send in the well-packed unit; at Airbag24, checking, repairing and testing usually take 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components and erases stored crash data. A function test follows at the end, after which your own unit is returned to you.

The order is binding, because disconnecting the battery and removing the unit may only be done after the readout.

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 5C0959655J get to Airbag24?

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

Put the printed repair order into the parcel and pack the unit shock-resistant.