Airbag control unit with part number 89170-12D40

What does the airbag control unit 89170-12D40 do?

The airbag control unit 89170-12D40 controls the restraint system (SRS) in the vehicle for Toyota. It reads the signals from the crash sensors, decides within milliseconds in an accident whether airbags and seatbelt pretensioners are triggered, and monitors the system constantly.

If the unit detects a fault, it appears on the airbag warning light in the instrument cluster. This is how you find out in everyday driving that something is wrong with the restraint system.

After an accident, the control unit stores crash data and locks itself. The sensor data is evaluated in the process, without you having to adjust anything.

Why does the control unit 89170-12D40 fail?

The most common cause is crash data stored after an accident, even if no airbag was deployed. Ageing electronic components, cold solder joints, moisture and corrosion on plug connections, and voltage spikes are also possible causes.

A normal diagnostic tool cannot delete the crash data. As long as it is stored in the control unit, the fault remains present with every readout.

The other causes concern the unit itself and its connections. Which of them applies in an individual case only becomes clear during the examination.

How can you tell that the 89170-12D40 is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently. An error message may also appear, the diagnostic tool cannot find the control unit, and the fault memory cannot be cleared. Such signs mean that airbags and seatbelt pretensioners may not deploy in an emergency.

The warning light is the signal you should react to. A light that comes on only now and then is no sign that everything is back in order.

Whether the control unit itself is affected is shown by the readout. A missing connection can also have other causes.

Which vehicles is the 89170-12D40 fitted in?

The control unit 89170-12D40 is fitted in these vehicles: Toyota Corolla E170 (2013-2018).

The models recorded with this control unit in our data are shown in the overview below.

• Toyota Corolla E170 (2013-2018)

Compare the part number on the label of the removed unit with this page, and you will know that it is the correct unit. Also have the fault memory read out before you remove the unit. Only this result shows whether the control unit is defective or a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 89170-02C70, 89170-12180, 89170-12G10, 89170-12N50.

How does the repair of the 89170-12D40 work?

At Airbag24, checking, repairing and testing usually take 3–4 working days. Beforehand, read out the fault memory, enclose the log and disconnect the battery before the control unit is removed. Then create the repair order online and send in the well-packed unit.

The sequence of steps serves your safety and is binding. Only after the battery has been disconnected is the control unit removed.

Airbag24 checks the unit on the test bench, replaces defective components and deletes the stored crash data. A function test follows, and your own unit is returned 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 89170-12D40 get to Airbag24?

You send in the control unit as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

Put the printed repair order into the parcel and pack the unit shockproof.