Airbag control unit with part number 89170-12E31

What does the airbag control unit 89170-12E31 do?

The airbag control unit 89170-12E31 is the central control unit of the SRS restraint system for Toyota. It evaluates the signals of the crash sensors, selects the suitable airbags and seatbelt pretensioners within milliseconds in an accident, and monitors the system continuously.

Detected faults are reported by the unit via the airbag warning light in the instrument cluster. The monitoring takes place without interruption.

After an accident it stores crash data and locks itself. Only a repair lifts the lock.

Why does the control unit 89170-12E31 fail?

With the 89170-12E31, the most common cause is crash data stored after an accident, even without a triggered airbag. A standard diagnostic tool cannot remove this data. In addition, aged components, cold solder joints, moisture and corrosion as well as voltage spikes play a role.

The crash data lies in the memory of the unit and stays there until it is removed. Airbag24 carries out this step as part of the repair.

• Ageing of electronic components
• Solder joints that have gone cold
• Moisture and rust at plug connections
• Voltage spikes from the vehicle electrical system

How can you tell that the 89170-12E31 is defective?

A defect in the 89170-12E31 can be recognised by an airbag warning light that lights permanently or intermittently in the instrument cluster, error messages in the instrument cluster, no connection being set up by the diagnostic tool, and a fault memory that cannot be cleared.

• Airbag warning light in the instrument cluster, permanent or intermittent
• Error message in the instrument cluster
• Diagnostic tool receives no connection to the control unit
• Fault memory cannot be cleared

With such a finding, airbags and seatbelt pretensioners may not trigger in an emergency. Each of these signs therefore deserves a prompt check.

Which vehicles is the 89170-12E31 fitted in?

The control unit 89170-12E31 is fitted in the following vehicles: Toyota Corolla E170 (2013-2018).

The list shows the vehicles known to us for this part number.

• Toyota Corolla E170 (2013-2018)

Compare the part number on the label of the removed unit with this page. That only confirms that it is the correct unit. Have the fault memory read out beforehand, because the result 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 89170-12E31 work?

Processing at Airbag24 takes 3–4 working days as a rule. First have the fault memory read out and attach the log, then disconnect the battery and only then remove the unit. Afterwards create a repair order online and send the unit in well packed.

Airbag24 examines the unit on the test bench, replaces defective components, erases the stored crash data and carries out a functional test. Afterwards the 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 89170-12E31 get to Airbag24?

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

The printed repair order goes into the parcel. Pack the control unit shockproof.