Airbag control unit with part number 89170-42381

What does the airbag control unit 89170-42381 do?

The airbag control unit 89170-42381 is the control unit of the restraint system (SRS) for Toyota. It monitors the crash sensors, decides in an event within milliseconds on airbags and seatbelt pretensioners, and keeps the system under constant watch. Faults are reported via the airbag warning light.

In normal operation, the monitoring runs unnoticed in the background. It only intervenes when measured values deviate from the specifications or a component fails.

After an accident, the unit creates crash data and locks itself. The data then stays in the memory and matters during diagnosis.

Why does the control unit 89170-42381 fail?

The most common cause is an entry in the stored crash data from an accident, even without a triggered airbag; an ordinary diagnostic tool does not delete it. Other causes are ageing components, dry solder joints, moisture and corrosion on plug connections, and voltage spikes from a weak battery or a jump start.

Electronics age, and over time components can weaken. A dry solder joint forms only an unreliable contact.

Penetrating moisture and corrosion attack plug connections. Voltage spikes add further strain on the electronics.

How can you tell that the 89170-42381 is defective?

If the airbag warning light in the instrument cluster lights up permanently or only intermittently, there is a fault. Fault messages appear alongside it, the diagnostic tool cannot reach the control unit, and the fault memory remains. With such symptoms, airbags and seatbelt pretensioners may fail to deploy in an emergency.

The light is the clearest signal the system gives. If it stays on, a check without delay is the right step.

The diagnostic tool is the most important tool here. If the connection fails, the cause still has to be established, because without a test it cannot be said what exactly is defective.

Which vehicles is the 89170-42381 fitted in?

The control unit 89170-42381 is fitted in these vehicles: Toyota RAV4 XA30 (2006-2009) and XA30 Facelift (2009-2013). When matching, the label on the unit is what counts.

The vehicles in the list are shown here for an overview:

• Toyota RAV4 XA30 (2006-2009)
• Toyota RAV4 XA30 Facelift (2009-2013)

Carry out the label comparison before removal, to make sure you have the correct unit. Also have the fault memory read out beforehand, because it shows whether the control unit or a connector or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 150300-8850, 89170-0P010, 89170-0P020, 89170-0P030, 89170-0P040, 89170-0P050.

How does the repair of the 89170-42381 work?

First have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit. Next, create a repair order online and send the well-packed unit in. Airbag24 tests it on the test bench, repairs defective components, clears crash data and carries out a function test; this usually takes 3–4 working days.

The sequence is binding for safety reasons.

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 89170-42381 get to Airbag24?

Shipping is either by parcel or by a UPS collection booked for an extra charge. Airbag24 then sends the repaired unit back to you by UPS.

The printed repair order must be included in the parcel, and the packaging must protect the unit well against impact.