Airbag control unit with part number 89170-0E400

What does the airbag control unit 89170-0E400 do?

The airbag control unit 89170-0E400 coordinates the SRS restraint system for Toyota. It processes the signals from the crash sensors, determines within milliseconds in an accident whether airbags and seatbelt pretensioners are triggered, and monitors the entire system.

If it detects a fault, it stores the fault and displays it via the airbag warning light. The reading on the instrument cluster is therefore the first hint you will get.

After an accident the unit stores crash data and locks itself. The lock affects the function of the control unit as a whole, which is why every fault search begins with a readout.

Why does the control unit 89170-0E400 fail?

Crash data stored after an accident is the most common cause, even if no airbag has deployed. A normal diagnostic tool does not erase it. Other possible causes include aged components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

Aged components and cold solder joints gradually weaken the electrical connection. Moisture and corrosion have a similar effect, especially at plug connectors.

Voltage spikes, for example from a weak battery or a jump start, can overload the electronics.

How can you tell that the 89170-0E400 is defective?

You can recognise a defect on the 89170-0E400 by the airbag warning light in the instrument cluster, which stays on permanently or intermittently. Fault messages appear alongside it, the diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared.

As long as these signs persist, airbags and seatbelt pretensioners may not deploy in a crash. The warning light is therefore a warning that you should have checked promptly.

Which vehicles is the 89170-0E400 fitted in?

The 89170-0E400 is fitted in these vehicles: Toyota Highlander XU70 (from 2019).

The following vehicles are on record for this part number:

• Toyota Highlander XU70 (from 2019)

Compare the number on the label of the removed unit with this page. This only confirms that it is the correct unit. Have the fault memory read out beforehand, because only that result 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 89170-0E690.

How does the repair of the 89170-0E400 work?

First have the fault memory read out and attach the log. Then disconnect the battery and remove the control unit.

In the next step you create a repair order online and send the unit in well packed. Airbag24 tests the unit on the test bench, replaces defective components, clears stored crash data and carries out a function test.

Processing at Airbag24 usually takes 3–4 working days. Your own unit is then returned 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 89170-0E400 get to Airbag24?

The control unit 89170-0E400 reaches Airbag24 as a parcel, either by your own dispatch or with a UPS collection that you book for an extra charge. The return after repair is made by UPS.

Put the printed repair order into the parcel and pack the unit so that it is protected against shocks.