Airbag control unit with part number 1EA 959 655 CD

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

The airbag control unit 1EA 959 655 CD is the control unit of the restraint system (SRS) for Volkswagen. It processes the measured values from the crash sensors, decides within milliseconds in a crash whether airbags and seatbelt pretensioners are triggered, and logs faults. After an accident it stores crash data and locks itself.

Monitoring runs throughout every journey. Faults found are entered in the fault memory and shown via the airbag warning light.

The lock is only lifted by the repair. You will find more about the process in the section on the repair.

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

The most common cause for the 1EA 959 655 CD is crash data stored after an accident, even if no airbag has triggered. Aged components, moisture and corrosion on plug connections, and voltage spikes are also possible causes.

Stored crash data remains in the unit after an accident, even if no airbag has triggered. A standard diagnostic tool cannot remove it.

Aged electronic components, cold solder joints and moisture at plug connections can also lead to failure. Voltage spikes, for example from a weak battery or jump-starting, are among the causes as well.

On 1EA control units, such an internal defect cannot be repaired. Airbag24 offers only the erasure of stored crash data for this part number.

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

You can recognise a defect on the 1EA 959 655 CD by the airbag warning light that lights up permanently or intermittently, by a fault message in the instrument cluster, by no connection to the diagnostic tool, or by a fault memory that cannot be erased.

The airbag warning light in the instrument cluster indicates faults. Whether it stays on permanently or only lights up intermittently does not matter for the decision: either is a reason to have the fault memory read out.

This is accompanied by fault messages in the instrument cluster. The diagnostic tool may then find no connection to the control unit, and the fault memory cannot be emptied. In an emergency, airbags and seatbelt pretensioners may therefore not be able to trigger.

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

The 1EA 959 655 CD is fitted in these vehicles: Volkswagen ID.3 E1 (2019-2023) and E1 Facelift (from 2023); Volkswagen ID.4 E2 (from 2020).

Here the assignment is shown as a list:

• Volkswagen ID.3 E1 (2019-2023)
• Volkswagen ID.3 E1 Facelift (from 2023)
• Volkswagen ID.4 E2 (from 2020)

Compare the part number on the label of the removed unit with this page, then you know that it is the correct unit. That comparison tells you nothing more. Therefore have the fault memory read out beforehand; only then does it become clear whether the control unit is defective or whether a plug or cable is the cause. If B2000 ("control unit defective") is displayed, no repair is possible, and you do not send the unit in.

For the same vehicles, we also repair control units with the part numbers 1EA 959 655 DR, 1EA 959 655 ER, 1EA959655EA.

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

First have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit 1EA 959 655 CD. Then create a repair order online and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days.

The unit is checked on the test bench at Airbag24, the stored crash data is erased, and a function test follows. Afterwards your own unit comes back to you.

If fault B2000 is stored, no repair is possible for control units with a 1EA part 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 CD get to Airbag24?

You send the control unit 1EA 959 655 CD as a parcel, or book a UPS collection for an extra charge. After the repair, Airbag24 returns the unit by UPS.

The printed repair order goes into the parcel. Pack the unit shockproof so that it arrives undamaged.