Airbag control unit with part number 89170-33E91

What does the airbag control unit 89170-33E91 do?

The airbag control unit 89170-33E91 is the central control unit of the restraint system (SRS) for Lexus. It evaluates the signals from the crash sensors and, in an emergency, decides within milliseconds which airbags and seatbelt pretensioners are triggered. It shows detected faults via the airbag warning light.

The unit monitors the system continuously. After an accident it stores crash data and locks itself.

Why does the control unit 89170-33E91 fail?

With the 89170-33E91, the most common cause is stored crash data after an accident, even if no airbag has deployed. Other causes are aged components, cold solder joints, moisture and corrosion, as well as voltage spikes.

Stored crash data cannot be erased with a standard diagnostic tool, but Airbag24 erases it during the repair. The other causes relate to ageing and wear of the electronics, poor contacts and electrical stress.

How can you tell that the 89170-33E91 is defective?

A defect shows itself through several signs that you can recognise directly in the vehicle and on the diagnostic tool. These include the airbag warning light, error messages and a fault memory that cannot be cleared.

• Airbag warning light in the instrument cluster lights up permanently or intermittently
• Error message in the instrument cluster
• Diagnostic tool cannot connect to the control unit
• Fault memory cannot be cleared

Airbags and seatbelt pretensioners may not be able to trigger in an emergency while such a defect exists. The warning light reports it, so you should arrange a check promptly.

Which vehicles is the 89170-33E91 fitted in?

The control unit 89170-33E91 is fitted in these vehicles: Lexus ES AXZH60 (from 2018). This list lets you quickly check whether your car is included.

The vehicles matching this part number are listed here:

• Lexus ES AXZH60 (from 2018)

Comparing the part number on the label of the removed unit with this page only confirms that it is the right unit; it does not identify the cause. Have the fault memory read out beforehand, because only the log 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 89170-06820, 89170-06850, 89170-06880, 89170-33B90, 89170-33C30, 89170-33C50.

How does the repair of the 89170-33E91 work?

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

Airbag24 checks 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. Processing at Airbag24 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 89170-33E91 get to Airbag24?

You send the control unit 89170-33E91 as a parcel or book a UPS collection for an extra charge. After the repair, UPS brings it back to you.

The printed repair order goes into the parcel, and you pack the unit shockproof.