Airbag control unit with part number 89170-33S20

What does the airbag control unit 89170-33S20 do?

The airbag control unit 89170-33S20 is the central control unit of the restraint system (SRS) of Lexus. It evaluates the crash sensors, decides in an accident whether airbags and seatbelt pretensioners are triggered, and monitors the system continuously. It reports faults via the airbag warning light.

After an accident the unit stores crash data and locks itself. The protective effect of the entire system depends on the function of this component.

Why does the control unit 89170-33S20 fail?

Stored crash data from an accident is the most common cause with the 89170-33S20, even if no airbag has deployed. A normal diagnostic tool cannot erase the crash data.

In addition, aged electronic components, cold solder joints and moisture at connector points can lead to failure. Corrosion acts on the same points.

Voltage spikes, for example from a weak battery or a jump start, are also among the causes. Airbag24 erases the crash data during the repair; you do not have to do anything for this.

How can you tell that the 89170-33S20 is defective?

A defect in the 89170-33S20 shows primarily as the airbag warning light in the instrument cluster, which stays on permanently or intermittently.

Accompanying signs can include an error message in the instrument cluster, a diagnostic tool with no connection to the control unit, and a fault memory that cannot be cleared. Each of these three signs points to a problem in the system that must not be ignored.

In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

Which vehicles is the 89170-33S20 fitted in?

The 89170-33S20 is fitted in these vehicles: Lexus ES AXZH60 (from 2018).

Here is an overview of the affected vehicles:

• 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 correct unit. Before sending it in, have the fault memory read out; only this result shows whether the control unit 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 89170-33S20 work?

First have the fault memory read out and attach the log. Then disconnect the battery. Only once the battery is disconnected do you remove the control unit 89170-33S20. Then create the repair order online, and send the unit off well packed. Processing at Airbag24 usually takes 3–4 working days.

At Airbag24 the unit is checked on the test bench, defective components are replaced, stored crash data is erased and a function test is carried out.

Your own unit is returned to you afterwards. 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 89170-33S20 get to Airbag24?

You organise the shipment to Airbag24 yourself, by parcel or with a UPS collection booked for an extra charge. After the repair, the control unit 89170-33S20 comes back by UPS.

Pack the unit shock-proof and enclose the printed repair order.