Airbag control unit with part number 1EA 959 655 AD

What does the airbag control unit 1EA 959 655 AD do?

The control unit 1EA 959 655 AD is the central control of the SRS for Seat. It processes the measured values of the crash sensors and, in an accident, triggers the appropriate airbags and seatbelt pretensioners within milliseconds.

It also checks the system throughout operation and displays faults on the airbag warning light.

After an accident, it stores crash data and locks itself.

Why does the control unit 1EA 959 655 AD fail?

Crash data stored after an accident is the most common cause of a failure, even if no airbag has triggered. Further causes are aged components, moisture and corrosion on plug connections, cold solder joints and voltage spikes, for example with a weak battery or jump-starting.

Crash data cannot be removed with usual diagnostic tools; that is why Airbag24 erases it during the repair.

Other internal defects cannot be repaired on control units with a 1EA number.

How can you tell that the 1EA 959 655 AD is defective?

You recognise a defect by the airbag warning light staying on permanently or lighting up intermittently, and by a fault message in the instrument cluster. If the diagnostic tool cannot connect, or the fault memory cannot be cleared, that also points to a defect.

With these signs, airbags and seatbelt pretensioners may not deploy in an emergency. The warning light reports the fault so that it is not overlooked.

• Airbag warning light stays on permanently or intermittently
• Fault message in the instrument cluster
• No connection to the diagnostic tool
• Fault memory cannot be cleared

Which vehicles is the 1EA 959 655 AD fitted in?

The 1EA 959 655 AD is fitted in these vehicles: Seat Leon 4 [KL] (from 2020). The part number on the removed unit remains decisive.

The list for this part number reads:

• Seat Leon 4 [KL] (from 2020)

Compare the number on the label with this page; then you know that it is the right unit. Have the fault memory read out, because only the log shows whether the control unit is defective or whether the cause is a plug or cable. If B2000 is shown, a repair is ruled out, and you do not send the unit in.

For the same vehicles, we also repair control units with the part numbers 1EA 959 655 BJ, 1EA 959 655 CH, 1EA 959 655 CK, 1EA 959 655 ED, 3Q0 959 655 CM, 3Q0959655AB.

How does the repair of the 1EA 959 655 AD work?

You have the fault memory read out and enclose the log in the parcel; then you disconnect the battery and remove the control unit. Online you create a repair order, then you send the well-packed unit in. Processing at Airbag24 usually takes 3–4 working days.

On the test bench at Airbag24, the crash data is removed before a function test concludes the work. Your own unit is then returned.

If B2000 is in the fault memory, a repair is not possible for control units with a 1EA number.

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 1EA 959 655 AD get to Airbag24?

A parcel is enough; alternatively, you book a UPS collection for an extra charge. UPS handles the return after the repair.

Enclose the printed repair order and pack the unit shockproof.