Airbag control unit with part number 89170-F4140

What does the airbag control unit 89170-F4140 do?

At Toyota, the 89170-F4140 controls the restraint system (SRS). It captures the signals from the crash sensors, decides in an accident within milliseconds on airbags and seatbelt pretensioners, and monitors the system continuously. Faults are shown via the airbag warning light.

While driving, the control unit works unnoticed in the background and reports only deviations.

After an accident the unit stores crash data, and it then locks itself.

Why does the control unit 89170-F4140 fail?

The most common cause is crash data that remain in the memory of the 89170-F4140 after an accident, even if no airbag has fired. Ordinary diagnostic tools do not erase them; Airbag24 removes them during the repair.

Other causes are:

• Age-related deterioration of the electronic components
• Cold solder joints
• Moisture and corrosion at the plug connectors
• Voltage spikes, for example from a weak battery or after a jump start

Which cause applies to your unit can only be determined by testing on the test bench.

How can you tell that the 89170-F4140 is defective?

The airbag warning light in the instrument cluster is the first sign: when it stays on permanently or flickers, there is a fault. Under certain circumstances error messages, a diagnostic tool without contact to the control unit or a fault memory that cannot be emptied are added. In an emergency, airbags and seatbelt pretensioners may not be able to trigger.

So that such symptoms do not go unnoticed, a prompt check is worthwhile rather than dismissing the light as a minor matter.

Which vehicles is the 89170-F4140 fitted in?

This 89170-F4140 belongs to the following vehicles: Toyota C-HR NGX10 (2017-2019).

Here are the vehicles we have on record for this part number:

• Toyota C-HR NGX10 (2017-2019)

Read out the fault memory before removal. Then you know whether plugs or cables can be ruled out as the cause, and you can compare the part number on the unit with this page.

For the same vehicles, we also repair control units with the part numbers 89170-F4210, 8917010110.

How does the repair of the 89170-F4140 work?

You first read out the fault memory, disconnect the battery and remove the 89170-F4140. Afterwards you create the repair order online. Processing of the 89170-F4140 at Airbag24 usually takes 3–4 working days.

The fault memory log belongs in the order. Take care when removing the unit not to damage the plug connections.

Airbag24 then checks the control unit on the test bench, replaces defective components and erases the crash data. A function test follows, and only then does your own unit go back.

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-F4140 get to Airbag24?

You send the control unit 89170-F4140 as a parcel to us, or you book a UPS collection for an extra charge. The return after the repair is made by UPS.

The printed repair order belongs in the parcel, and the unit should be packed shockproof.