Airbag control unit with part number 89170-52740

What does the airbag control unit 89170-52740 do?

The airbag control unit 89170-52740 controls the restraint system (SRS) in Toyota. It processes the crash sensor data and determines within milliseconds in an accident which airbags and seatbelt pretensioners are triggered.

During operation the unit constantly checks its surroundings within the system. If it detects a malfunction, it reports this via the airbag warning light in the instrument cluster.

For accident documentation, it writes crash data after an impact and then remains locked. Only a repair lifts this lock.

Why does the control unit 89170-52740 fail?

The most common cause is stored crash data from an accident, even without an airbag being triggered. Ageing components, moisture, cold solder joints and voltage spikes on the 89170-52740 are further causes.

Crash data stays in the memory, because a standard diagnostic tool cannot erase it. Airbag24 erases it in the course of the repair.

The other causes relate to electronics and connections. Over time components age, solder joints can go cold, and moisture causes corrosion at plug connectors.

Voltage spikes, for example from a weak battery or from connecting a jump start, also affect the unit.

How can you tell that the 89170-52740 is defective?

A defect in the 89170-52740 can be recognised by the airbag warning light, if it stays on permanently or intermittently. Further signs include a fault message in the instrument cluster, no connection to the diagnostic tool and a fault memory that cannot be cleared.

In such cases airbags and seatbelt pretensioners may fail to trigger in an emergency. That calls for a check, even if the car otherwise behaves normally.

The warning light is the system's visible signal, and it must not be ignored.

Which vehicles is the 89170-52740 fitted in?

The 89170-52740 is fitted in these vehicles: Toyota Yaris XP90 (2005-2009) and XP90 Facelift (2009-2011). This assignment applies to exactly this part number 89170-52740.

Here is the list of vehicles recorded for this part number:

• Toyota Yaris XP90 (2005-2009)
• Toyota Yaris XP90 Facelift (2009-2011)

On the removed unit, compare the part number on the label with this page. This ensures that you have the right control unit. It does not show the cause. Only the fault memory, which you have read out beforehand, shows whether the control unit is defective or whether a plug or cable is responsible.

For the same vehicles, we also repair control units with the part numbers 212986-105, 212986-110, 220749-101, 89170-0D170, 89170-0D230, 89170-0D440.

How does the repair of the 89170-52740 work?

Processing of the 89170-52740 at Airbag24 usually takes 3–4 working days, counting only checking, repairing and testing. The steps before that are reading out, removal and sending in.

First have the fault memory read out and attach the log to the unit. Then disconnect the battery and remove the control unit. Next create the repair order online and send in the unit well packed.

Airbag24 checks the unit on the test bench, replaces defective components, erases the crash data and carries out a function test. Afterwards the unit comes 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 89170-52740 get to Airbag24?

You send the 89170-52740 to Airbag24 as a parcel or book a UPS collection for an extra charge. After the repair the unit comes back to you via UPS.

The printed repair order goes in the parcel, and the control unit is packed shock-resistant.