Airbag control unit with part number 1J0 909 608

What does the airbag control unit 1J0 909 608 do?

The airbag control unit 1J0 909 608 is the central control unit of the restraint system (SRS) for Volkswagen. It evaluates the signals from the crash sensors and determines in an accident, in a very short time, which airbags and seatbelt pretensioners are triggered.

The control unit checks the entire system continuously and shows faults via the airbag warning light. The manufacturer's number Continental 5WK4154 is additionally printed on the housing.

After an accident the unit stores crash data and locks itself. The following section deals with the crash data.

Why does the control unit 1J0 909 608 fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed; a standard diagnostic tool cannot clear it. Other causes include aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Stored crash data therefore remains in the control unit, regardless of whether an airbag has deployed. Common diagnostic tools cannot remove it.

Aged electronics and cold solder joints impair the function over time. Moisture and corrosion at plug connections additionally disturb the contact.

Voltage spikes arise, for example, from a weak battery or a jump start, and they stress the unit.

How can you tell that the 1J0 909 608 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. In addition, an error message appears, and the diagnostic tool finds no connection to the control unit.

• Airbag warning light lights up permanently or intermittently
• Error message in the instrument cluster
• Diagnostic tool gets no connection to the control unit
• Fault memory cannot be cleared

In an emergency, airbags and seatbelt pretensioners may not deploy. Please have the system checked promptly.

Which vehicles is the 1J0 909 608 fitted in?

The 1J0 909 608 is fitted in these vehicles: Volkswagen Golf 4 (1J); Volkswagen Golf GTI Mk4; Volkswagen Golf Variant 4 (1J5).

The vehicles for this part number are listed below:

• Volkswagen Golf 4 (1J)
• Volkswagen Golf GTI Mk4
• Volkswagen Golf Variant 4 (1J5)

Compare the part number on the label of the removed unit with this page to be sure that it is the right unit. Also have the fault memory read out in advance, because the log shows whether the control unit itself is defective or whether a connector or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 0261207190, 1C0 909 605 A, 1C0 909 605 F, 1J0 909 603 AN, 1J0 909 605 A, 1J0 909 609.

How does the repair of the 1J0 909 608 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit. Next, create a repair order online and send in the well-packed unit.

Airbag24 checks the unit on the test bench, replaces defective components where necessary, erases the stored crash data and carries out a function test. Checking, repairing and testing at Airbag24 usually takes 3–4 working days. After that, your own unit comes 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 1J0 909 608 get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. Airbag24 returns the repaired unit by UPS. The printed repair order belongs in the parcel, and you pack the control unit shock-resistant.

Suitable packing material prevents the unit from being damaged in transit.