Airbag control unit with part number 5QF959655AL

What does the airbag control unit 5QF959655AL do?

The airbag control unit 5QF959655AL forms the central control unit of the restraint system (SRS) in Seat. It processes the messages from the crash sensors, determines within milliseconds which airbags and seatbelt pretensioners fire, and monitors the system continuously. After an accident, it stores crash data and locks itself.

Faults are indicated by the unit via the airbag warning light in the instrument cluster. The system is checked constantly during operation so that a fault becomes visible as quickly as possible.

Why does the control unit 5QF959655AL fail?

The most common cause is crash data that remains stored in the 5QF959655AL after an accident, even if no airbag was triggered; a normal diagnostic tool cannot get at it. Other causes are aged electronics, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Plug connections in particular are vulnerable, because moisture and salt gnaw at the contacts over the years. Solder joints on the circuit board can also give way over time and interrupt connections.

Voltage spikes act directly on the electronics. They arise, for example, from a weak battery or from jump-starting.

How can you tell that the 5QF959655AL is defective?

A defect in the 5QF959655AL shows up as the airbag warning light in the instrument cluster lighting up constantly or intermittently, as an error message in the instrument cluster, as a diagnostic tool without connection to the control unit, and as a fault memory that cannot be erased. In this state, airbags and seatbelt pretensioners may fail to trigger in an emergency.

These signs appear singly or together:

• Airbag warning light stays on constantly or intermittently
• Error message in the instrument cluster
• Diagnostic tool cannot find the control unit
• Fault memory remains, even after an attempt to erase it

Take the warning light seriously, because it is the warning the system itself gives about a fault.

Which vehicles is the 5QF959655AL fitted in?

The control unit 5QF959655AL is fitted in the following vehicles: Seat Ibiza 5 [6F] (2017-2021) and 5 [6F] Facelift (from 2021).

Below are the vehicles stored for this part number:

• Seat Ibiza 5 [6F] (2017-2021)
• Seat Ibiza 5 [6F] Facelift (from 2021)

Compare the part number on the label of the removed unit with this page, so you know that you have the correct unit. Have the fault memory read out beforehand. Only this result shows whether the control unit itself is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 5QF 959 655 L, 5QF 959 655 N, 5QF959655AE, 5QF959655AG, 5QF959655AM, 5QF959655M.

How does the repair of the 5QF959655AL work?

First have the fault memory read out on the 5QF959655AL 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. Processing at Airbag24 usually takes 3–4 working days.

On the test bench, Airbag24 checks the unit, repairs the defective components, erases the stored crash data and carries out a function test. 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 5QF959655AL get to Airbag24?

You send the control unit 5QF959655AL as a parcel, or you arrange a UPS collection for an extra charge. Airbag24 sends your own unit back by UPS after the repair.

The printed repair order goes into the parcel, and the unit must be packed shock-proof.