Airbag control unit with part number 89170-F4270

What does the airbag control unit 89170-F4270 do?

The airbag control unit 89170-F4270 is the central control unit of the restraint system (SRS) in Toyota. It processes the crash sensors, determines in an accident within milliseconds the triggering of airbags and seatbelt pretensioners, and monitors the system continuously. It indicates faults via the airbag warning light.

After an accident it stores crash data and is locked afterwards. Only the repair lifts the lock.

The unit is connected to sensors and triggers by wiring. In everyday use you hardly notice it.

Why does the control unit 89170-F4270 fail?

Crash data from an earlier accident is the most common cause, even if no airbag has fired. An ordinary diagnostic tool does not remove it from the memory. Additional causes include ageing components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes from a weak battery or a jump-start.

This data remains even if the vehicle is then used without restriction.

Ageing electronics, cold solder joints, and moisture or corrosion at the plug connections worsen the contact. Voltage spikes add further stress.

How can you tell that the 89170-F4270 is defective?

Signs are an airbag warning light that stays on permanently or intermittently, a fault message in the instrument cluster, a diagnostic tool with no connection to the control unit, and a fault memory that cannot be cleared. With these signs, airbags and seatbelt pretensioners may not fire in an emergency.

The warning light is a clear indication from the vehicle. That is exactly why it should not be ignored when it stays on permanently or comes back on.

The fault message in the instrument cluster also points to the malfunction and should be taken seriously.

Which vehicles is the 89170-F4270 fitted in?

The airbag control unit 89170-F4270 is fitted in these vehicles: Toyota C-HR NGX10 Facelift (2019-2023).

The vehicles recorded for this part number with us are listed below.

• Toyota C-HR NGX10 Facelift (2019-2023)

Compare the part number on the label of the removed unit with this page. This ensures that you have the right unit. Have the fault memory read out beforehand, because only this 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-F4210, 8917010110.

How does the repair of the 89170-F4270 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit. Afterwards create the repair order online and send the well-packed unit in.

Airbag24 checks the unit on the test bench, repairs defective components, erases stored crash data and carries out a function test. Afterwards your own unit goes back to you.

Processing at Airbag24 takes 3–4 working days as a rule. This time covers only the work done in-house.

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-F4270 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.

Put the printed repair order into the parcel and pack the unit shock-proof.