Airbag control unit with part number 89170-02B20

What does the airbag control unit 89170-02B20 do?

The airbag control unit 89170-02B20 forms the central switching point of the restraint system (SRS) for Toyota. It evaluates the sensor signals, determines in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously for faults.

If it detects a fault, it alerts the driver via the airbag warning light in the instrument cluster. The monitoring is therefore a constant self-check of the system.

After an accident, the unit stores crash data and is then locked.

Why does the control unit 89170-02B20 fail?

The most common cause is crash data stored after an accident, even if no airbag has triggered. A standard diagnostic tool cannot remove it. Ageing components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes are also possible causes.

Stored crash data is the most common reason for a failure, even though the airbags did not fire in the accident. After the event, nothing of it is noticeable while driving.

The other causes concern the electronics. Components age over time, solder joints go cold, and moisture or corrosion affect plug connections. Voltage spikes, for example from a weak battery or jump-starting, can also cause damage.

How can you tell that the 89170-02B20 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, an error message is displayed, the diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared.

• airbag warning light permanently or intermittently on
• 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 then fail to trigger. Therefore take a lit warning light seriously and have it checked promptly.

Which vehicles is the 89170-02B20 fitted in?

The 89170-02B20 is fitted in these vehicles: Toyota Corolla E140 (2006-2013).

The vehicles in detail:

• Toyota Corolla E140 (2006-2013)

A comparison of the part number on the label of the removed unit with this page only ensures it is the right unit. Whether the control unit is defective or whether a plug or cable is the cause is shown only by reading out the fault memory. Have this done before removal.

For the same vehicles, we also repair control units with the part numbers 89170-0F032, 89170-12160.

How does the repair of the 89170-02B20 work?

Processing at Airbag24 usually takes 3–4 working days. Beforehand, you read out the fault memory and enclose the log, disconnect the battery and only then remove the control unit. Then create a repair order online and send the well-packed unit in.

Airbag24 checks the unit on the test bench, replaces defective components, deletes the stored crash data and carries out a function test. Your own unit then 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 89170-02B20 get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 sends the unit back to you by UPS.

Enclose the printed repair order in the parcel and pack the unit shock-proof.