Airbag control unit with part number 89170-74190

What does the airbag control unit 89170-74190 do?

The airbag control unit 89170-74190 is the central control unit of the restraint system for Toyota. It evaluates signals from the crash sensors, decides in a crash within milliseconds on the triggering of airbags and seatbelt pretensioners, and monitors the system continuously. After a crash it stores crash data and locks itself.

If the unit detects a fault, the airbag warning light in the instrument cluster comes on.

The decision has to be made so quickly that it requires constant self-checking. The unit therefore checks continuously whether it can still perform its task.

Why does the control unit 89170-74190 fail?

Most often it is due to crash data from an earlier accident, even without a triggered airbag; a normal diagnostic tool cannot erase it. Also to be considered are ageing components, cold solder joints, moisture at plug connectors and voltage spikes.

The memory records the incident, regardless of whether an airbag fired.

Electronics age over time, and solder joints can go cold or break. Moisture penetrates plugs and promotes corrosion.

A weak battery or a jump-start can cause voltage spikes that stress the electronics. Which cause applies is established by the check.

How can you tell that the 89170-74190 is defective?

A defect shows up mainly as the airbag warning light in the instrument cluster, as error messages, or as a diagnostic tool without connection. Airbags and seatbelt pretensioners may then possibly not deploy in an emergency.

Typical signs are:

• airbag warning light stays on constantly or intermittently
• error message in the instrument cluster
• diagnostic tool gets no connection to the control unit
• fault memory cannot be cleared

Each of these signs is a clear indication that the system needs checking. The cause, however, only becomes apparent from reading out the fault memory.

Which vehicles is the 89170-74190 fitted in?

You can find the vehicle details here. For Toyota, the control unit 89170-74190 is fitted in these vehicles: Toyota iQ KGJ10 (2008-2015).

The vehicles follow as a list:

• Toyota iQ KGJ10 (2008-2015)

Two steps are sensible before removal. Comparing the part number on the unit with this page only confirms that it is the right part. Having the fault memory read out, however, 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 150300-2193, 89170-74020, 89170-74140.

How does the repair of the 89170-74190 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 89170-74190. You create the repair order online, then send in the packed unit.

Work at Airbag24 usually takes 3–4 working days, because the unit is checked, repaired if necessary, and then tested.

At Airbag24 the unit is examined on the test bench, 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 89170-74190 get to Airbag24?

You send the control unit 89170-74190 in as a parcel, or book a UPS collection for an extra charge. After the repair it comes back to you by UPS.

The printed repair order goes into the parcel; pack the unit shock-proof.