Airbag control unit with part number 89170-33N80

What does the airbag control unit 89170-33N80 do?

The airbag control unit 89170-33N80 is the central control unit of the restraint system (SRS) for Lexus. It evaluates the signals from the crash sensors, decides within milliseconds in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. After an accident it stores crash data and locks itself.

The crash sensors continuously deliver their measurements to the control unit. Its evaluation has to be fast enough that the decision is made in time in an emergency; the unit is designed precisely for this.

The control unit reports faults in the system via the airbag warning light in the instrument cluster. Monitoring runs in the background; you do not need to set anything.

Why does the control unit 89170-33N80 fail?

On the 89170-33N80, the most common cause after an accident is stored crash data, even if no airbag has deployed; a standard diagnostic tool cannot erase it. In addition, ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or a jump start, may be causes.

After an accident the control unit stores the crash data and then remains locked. During the repair at Airbag24, stored crash data is deleted.

The other causes act over a longer period. Electronics age, solder joints can go cold, and moisture or corrosion at the plugs leads to poor contact. Voltage spikes can also strain the unit, for example when starting with outside help.

How can you tell that the 89170-33N80 is defective?

A defect on the 89170-33N80 shows when the airbag warning light in the instrument cluster stays on permanently or intermittently, an error message appears, the diagnostic tool cannot reach the control unit, or the fault memory cannot be cleared. Airbags and seatbelt pretensioners may then fail to deploy in an emergency.

The warning light is the most important signal, because it shows the state of the system directly in your field of view. Typical signs are:

• The airbag warning light stays on or keeps coming on.
• An error message appears in the instrument cluster.
• A diagnostic tool cannot find the control unit.
• The fault memory cannot be cleared.

If the warning light comes on, have the system checked promptly.

Which vehicles is the 89170-33N80 fitted in?

The control unit 89170-33N80 is fitted in these vehicles: Lexus ES AXZH60 (from 2018).

The following overview shows the vehicles that Airbag24 assigns to this part number.

• Lexus ES AXZH60 (from 2018)

Both steps will help you. Compare the part number on the label of the removed unit with this page; this only ensures that it is the right unit. Have the fault memory read out beforehand, because only that 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 89170-33N80 work?

For the repair of the 89170-33N80, first have the fault memory read out and enclose the log. Then disconnect the battery, and only then remove the control unit and create a repair order online. Processing at Airbag24 usually takes 3–4 working days.

The sequence is prescribed for safety reasons. The control unit may only be removed after the battery has been disconnected.

At Airbag24 the team tests the unit on the test bench and replaces defective components. Stored crash data is deleted, followed by a function test. The processing time applies only to testing, repairing and checking at Airbag24.

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 89170-33N80 get to Airbag24?

You send the control unit 89170-33N80 as a parcel, or book a UPS collection for an extra charge. After the repair Airbag24 sends it back by UPS.

Put the printed repair order into the parcel and pack the control unit so that it withstands knocks before you send it.