Airbag control unit with part number 1K0909605AC

What does the airbag control unit 1K0909605AC do?

The airbag control unit 1K0909605AC runs the entire restraint system (SRS) in the vehicle of Volkswagen. It analyses the signals from the crash sensors, decides in a crash within milliseconds on the triggering of airbags and seatbelt pretensioners, and monitors the system continuously. After a crash, it stores crash data and locks itself.

The unit detects a fault itself and shows it via the airbag warning light. To do this, it checks sensors, wiring and the power supply during operation.

Why does the control unit 1K0909605AC fail?

The most common cause is stored crash data after a crash, even if no airbag has deployed; a normal diagnostic tool cannot delete it. Aged electronic components, cold solder joints, moisture and corrosion on plug connections, and voltage spikes can also be causes. Airbag24 deletes the crash data during the repair.

A fault search that ignores the crash data is therefore incomplete, because the data remains in the memory.

The other causes act on the electronics themselves: components age, solder joints become brittle, and moisture causes contacts to corrode. Voltage spikes arise, for example, from a weak battery or after a jump start.

How can you tell that the 1K0909605AC is defective?

Typical signs are an airbag warning light that stays on permanently or intermittently, an error message in the instrument cluster, a diagnostic tool without connection to the control unit, and a fault memory that cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

These signs can occur individually or together:

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

The warning light reports the defect itself. It is therefore enough to watch for it and have the fault memory read out promptly.

Which vehicles is the 1K0909605AC fitted in?

The airbag control unit 1K0909605AC is fitted in these vehicles: Volkswagen Jetta 5 (2005-2010). What matters is the control unit with exactly this number, not a device that looks similar.

The vehicles for this number can be found in the following list:

• Volkswagen Jetta 5 (2005-2010)

Compare the part number on the label of the removed unit with this page; this confirms that you have the right unit. Have the fault memory read out beforehand, because only the log shows whether the control unit is defective or whether a plug or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 1K0 909 605 T, 1K0909605AB, 1K0909605H, 1K0909605P, 1K0909605R.

How does the repair of the 1K0909605AC work?

First have the fault memory read out and attach the log. Then disconnect the battery before you remove the control unit. Afterwards, create a repair order online and send the unit in well packed.

Airbag24 checks the unit on the test bench, repairs defective components, deletes stored crash data and carries out a function test. Processing takes 3–4 working days as a rule, after which 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 1K0909605AC get to Airbag24?

You send the unit as a parcel, or book a UPS collection for an extra charge. After the repair, Airbag24 sends it back to you by UPS. Put the printed repair order into the parcel and pack the unit shockproof.

A sturdy carton with enough filling material protects the housing during shipping.