Airbag control unit with part number 89170-04520

What does the airbag control unit 89170-04520 do?

The airbag control unit 89170-04520 forms the central control unit of the SRS system of Toyota. It evaluates the signals from the crash sensors and triggers the appropriate airbags and seatbelt pretensioners within milliseconds in a crash. After an accident it stores crash data and locks itself.

It also continuously monitors the entire system. It shows any faults it finds via the airbag warning light in the instrument cluster.

If the unit fails, the restraint system no longer works reliably in an emergency, even if the airbags and seatbelt pretensioners are themselves in order.

Why does the control unit 89170-04520 fail?

Most often the fault is caused by crash data stored after an accident, even when no airbag has deployed. A normal diagnostic tool cannot erase it. Other causes are aged components, cold solder joints, moisture and corrosion at the plugs, and voltage spikes from a weak battery or jump-starting.

Stored crash data is therefore not always linked to visible damage or a deployed airbag, which is exactly what makes the connection hard to recognise.

The other causes concern the electronics themselves. Aged components and corrosion weaken them over time, whereas voltage spikes can disrupt them suddenly.

How can you tell that the 89170-04520 is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently. The instrument cluster also shows a fault message, the diagnostic tool does not find the control unit, and the fault memory remains.

This light signals that the restraint system is not in order. In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

Please have the warning checked promptly before you continue driving.

Which vehicles is the 89170-04520 fitted in?

The control unit 89170-04520 is fitted in these vehicles: Toyota Tacoma N200 (2004-2015).

The overview below shows the vehicles in detail:

• Toyota Tacoma N200 (2004-2015)

First compare the part number on the label of the removed unit with this page. That only ensures that it is the right unit. Also have the fault memory read out beforehand, because only that result shows whether the control unit is defective or a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 89170-04420, 89170-04570, 89170-04600, 89170-04650.

How does the repair of the 89170-04520 work?

First have the fault memory read out and attach the log to the unit. Then disconnect the battery and only then remove the control unit. Next, create a repair order online, pack the unit well and send it in; the processing at Airbag24 usually takes 3–4 working days.

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

The 3–4 working days refer only to the testing, repair and function test at Airbag24. 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 89170-04520 get to Airbag24?

Either you send the unit as a parcel, or you book a UPS collection for an extra charge. Airbag24 returns it to you by UPS after the repair.

Place the printed repair order in the parcel and pad the unit shock-proof.