Airbag control unit with part number 89170-33T70

What does the airbag control unit 89170-33T70 do?

The airbag control unit 89170-33T70 forms the central control of the restraint system (SRS) in vehicles of Lexus. It evaluates the crash sensors, selects the appropriate airbags and seatbelt pretensioners in an accident, and monitors the system permanently.

Triggering and monitoring run through the same unit, which is why a fault becomes visible at a central point.

After an accident, the unit stores crash data and locks itself.

Why does the control unit 89170-33T70 fail?

The most common cause of a failure of the 89170-33T70 is stored crash data, which are present even if no airbag has deployed; a normal diagnostic tool does not erase them. Further triggers are ageing electronics, cold solder joints, moisture and corrosion at connectors, and voltage spikes.

The event itself leaves the crash data in the memory of the unit.

The other causes are technical in nature. Components age, solder joints can break, moisture and corrosion affect contacts, and voltage spikes, for example from jump-starting, disturb the electronics.

How can you tell that the 89170-33T70 is defective?

A defect in the 89170-33T70 shows when the airbag warning light on the instrument cluster lights up permanently or intermittently. An error message on the instrument cluster, a diagnostic tool without a connection to the control unit or a fault memory that cannot be cleared also indicate a defect.

The airbag warning light on the instrument cluster is the first visible sign for you. It lights up as soon as the control unit registers a fault in the system, and it stays on until the fault is rectified.

If the control unit is defective, the airbags and seatbelt pretensioners may not trigger in an emergency.

Which vehicles is the 89170-33T70 fitted in?

The airbag control unit 89170-33T70 is fitted in these vehicles: Lexus ES AXZH60 (from 2018).

The list below names the vehicles that match.

• Lexus ES AXZH60 (from 2018)

First compare the part number on the label of the removed unit with this page, so that you know you have the correct unit in front of you. Be sure to have the fault memory read out before removal, because only this result shows whether the control unit itself is defective or whether a connector or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 89170-06820, 89170-06850, 89170-06880, 89170-33B90, 89170-33C30, 89170-33C50.

How does the repair of the 89170-33T70 work?

You have the fault memory read out, enclose the log and disconnect the battery; only then do you remove the 89170-33T70. Afterwards, you create a repair order online and send the unit in well packed.

Airbag24 checks the unit on the test bench and replaces defective components. The stored crash data are erased, and then the function test follows. Finally, your own unit reaches you again.

The work at Airbag24 on checking, repairing and testing usually takes 3–4 working days. 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 89170-33T70 get to Airbag24?

You post the control unit 89170-33T70 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 sends it back by UPS.

Pack the unit shock-proof and put the printed repair order into the parcel.