Airbag control unit with part number 89170-12D00

What does the airbag control unit 89170-12D00 do?

The airbag control unit 89170-12D00 is the central control unit of the restraint system (SRS) for Toyota. It evaluates the signals from the crash sensors and, in an accident, decides within fractions of a second which airbags and seatbelt pretensioners fire. It also monitors the entire system continuously and reports faults via the airbag warning light.

The sensors continuously supply the unit with measurements, and the evaluation runs in the background without interruption. The result is a decision about which restraint devices are to be triggered, and this decision forms the core of the protective function.

After an accident the unit stores crash data and locks itself. A reported fault is therefore worth checking promptly, because the restraint system is fully available only when the control unit works flawlessly.

Why does the control unit 89170-12D00 fail?

For the 89170-12D00, the most common cause is crash data stored after an accident, even if no airbag has deployed; a standard diagnostic tool cannot erase it. Other causes are ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Crash data remain in the unit after an accident, even if the airbags and seatbelt pretensioners were left untouched. A standard diagnostic tool cannot be made to remove it, which is why the fault memory stays occupied.

Electronics age, and components lose reliability over time. Cold solder joints, moisture and corrosion on plugs, and voltage spikes in the vehicle electrical system, for example from a weak battery or a jump-start, can likewise cause faults. Which cause applies in each case is only established by the check.

How can you tell that the 89170-12D00 is defective?

A defective 89170-12D00 reveals itself through the airbag warning light in the instrument cluster staying on permanently or intermittently, through an error message in the instrument cluster, through a missing connection to the diagnostic tool, and through a fault memory that cannot be cleared.

If the warning light is on, airbags and seatbelt pretensioners may fail to deploy in an emergency. The warning therefore concerns the protective effect of the whole system, even if the vehicle behaves inconspicuously in everyday use.

If the diagnostic tool stays silent and the fault memory cannot be reset, that is a clear sign that the finding needs closer investigation. The warning light indicates the defect and calls for a check.

Which vehicles is the 89170-12D00 fitted in?

The control unit 89170-12D00 is fitted in these vehicles: Toyota Corolla E170 (2013-2018).

The allocation covers the following models:

• Toyota Corolla E170 (2013-2018)

Compare the part number on the label of the removed unit with this page, because that only confirms that you have the right unit in front of you. Also have the fault memory read out beforehand, because only the log shows whether the control unit is defective or whether 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 89170-12D00 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 89170-12D00.

Airbag24 checks the unit on the test bench, repairs defective components, erases stored crash data and carries out a function test. Processing usually takes 3–4 working days at Airbag24. Afterwards 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 89170-12D00 get to Airbag24?

You send the control unit 89170-12D00 in a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends it back by UPS.

Enclose the printed repair order in the parcel and pack the unit shockproof.