Airbag control unit with part number 89170-33D40

What does the airbag control unit 89170-33D40 do?

The airbag control unit 89170-33D40 controls the restraint system (SRS) for Lexus. It evaluates the crash sensors, decides in an accident within milliseconds on triggering airbags and seatbelt pretensioners, and monitors the system continuously. After an accident it stores crash data and locks itself.

The monitoring covers all components that belong to the system. If the unit detects a fault, the airbag warning light in the instrument cluster lights up.

Why does the control unit 89170-33D40 fail?

Most often the cause is stored crash data that was saved in the unit after an accident, even if no airbag has triggered. These cannot be cleared with an ordinary diagnostic tool. Other causes include ageing components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or a jump start.

With crash data, trying to clear it with ordinary tools does not help.

The electronics themselves age, solder joints can go cold, and moisture attacks contacts. Voltage spikes from the vehicle electrical system add further stress.

How can you tell that the 89170-33D40 is defective?

The airbag warning light in the instrument cluster lights constantly or intermittently, an error message appears in the instrument cluster, the diagnostic tool cannot reach the control unit, and the fault memory cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then possibly fail to deploy.

The warning light is the most visible sign of a fault.

If the diagnostic tool cannot reach the control unit, that is likewise a reason to have the finding checked.

Which vehicles is the 89170-33D40 fitted in?

The airbag control unit 89170-33D40 is fitted in these vehicles: Lexus ES AXZH60 (from 2018). The list only roughly indicates whether your car is affected.

The vehicles known to us for this number are listed here:

• Lexus ES AXZH60 (from 2018)

Compare the part number on the label of the removed unit with this page; this only tells you that it is the right unit. Have the fault memory read out beforehand. Only this log shows whether the control unit itself 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 89170-33D40 work?

First have the fault memory read out and enclose the log, then disconnect the battery and remove the control unit. Afterwards you create the repair order online and pack the unit well. Airbag24 checks it on the test bench, replaces defective components, deletes stored crash data and carries out a functional test; this usually takes 3–4 working days.

The order is mandatory for safety reasons. You read out the fault memory before disconnecting the battery; you remove the control unit only after that.

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 89170-33D40 get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends it back to you by UPS. The printed repair order goes into the parcel.

Pack the unit shock-resistant so that it withstands transport without damage.