Airbag control unit with part number 89170-F4200

What does the airbag control unit 89170-F4200 do?

The airbag control unit 89170-F4200 controls the restraint system (SRS) at Toyota. It evaluates the crash sensors, decides within a fraction of a second in an accident on airbags and seatbelt pretensioners, and monitors the system continuously. After an accident it stores crash data and locks itself.

The monitoring runs continuously, even during normal driving. If the control unit detects a fault, it reports it via the airbag warning light in the instrument cluster, so that you notice the fault.

Why does the control unit 89170-F4200 fail?

The most common cause is crash data stored after an accident, even if no airbag has been triggered. Other causes are ageing electronic components, dry solder joints, moisture and corrosion at plug connections, and voltage spikes, for example with a weak battery or a jump start.

Crash data cannot be erased with a normal diagnostic tool. During the repair, Airbag24 removes it from the unit's memory.

Electronics age over time, and solder joints can go cold. If moisture gets into the plugs, corrosion forms and disturbs the contact.

How can you tell that the 89170-F4200 is defective?

A defect shows up as the airbag warning light in the instrument cluster, which lights up permanently or intermittently, as a fault message in the instrument cluster, as a diagnostic tool without a connection to the control unit, and as a fault memory that cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may not be able to deploy. A lit warning light is therefore a reason to have the vehicle checked promptly.

The warning light deserves your attention, because it reports the defect itself.

Which vehicles is the 89170-F4200 fitted in?

The airbag control unit 89170-F4200 is fitted in these vehicles: Toyota C-HR NGX10 Facelift (2019-2023).

The assignment on this page looks like this in detail:

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

Compare the part number on the label of the removed unit with this page. This only ensures that you have the correct unit in front of you. Also have the fault memory read out before removal. Only this 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-F4210, 8917010110.

How does the repair of the 89170-F4200 work?

First have the fault memory read out and attach the log. Then disconnect the battery and only afterwards remove the control unit 89170-F4200. Online, create a repair order and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days.

On the test bench the unit is examined, defective components are replaced, stored crash data is erased and a function test is carried out. 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-F4200 get to Airbag24?

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

Put the printed repair order in the parcel, and pack the control unit shock-proof.