Airbag control unit with part number 89170-48490

What does the airbag control unit 89170-48490 do?

In the restraint system (SRS) of Lexus, the airbag control unit 89170-48490 acts as the central switching point. It reads the messages from the crash sensors and determines which airbags and seatbelt pretensioners are triggered in an accident; this happens in fractions of a second.

In addition, the unit checks the system constantly and reports faults via the airbag warning light in the instrument cluster. This makes it the point where every deployment is decided.

After an accident, it stores crash data and locks itself.

Why does the control unit 89170-48490 fail?

The crash data stored after an accident is the most common cause, even if no airbag has deployed. Added to this are ageing components, cold solder joints, moisture and corrosion on plug connections, and voltage spikes, for example in the case of a weak battery or a jump start.

Crash data cannot be erased with an ordinary diagnostic tool, so such an attempt does not solve anything. The other causes concern the electronics and their connections: components age, solder joints can be cold, moisture attacks contacts, and voltage spikes stress the electronics.

How can you tell that the 89170-48490 is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently. In addition, there is a fault message in the instrument cluster, no connection to the diagnostic tool, and a fault memory that cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may then not deploy. A lit warning light is therefore not a cosmetic issue, but an indication of a disturbed system.

Which vehicles is the 89170-48490 fitted in?

The control unit 89170-48490 is fitted in these vehicles: Lexus RX AL20 (2015-2019). The information applies to this part number and the make Lexus.

The vehicle list can be found here:

• Lexus RX AL20 (2015-2019)

Compare the part number on the label of the removed unit with this page, and you will know that it is the correct control unit. This comparison does not provide any finding on the cause. Therefore have the fault memory read out beforehand, because only that result 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 89170-0E021, 89170-48210, 89170-48211, 891700000000000016768827392, 89170000000000005112856576.

How does the repair of the 89170-48490 work?

First have the fault memory read out and attach the log. Then disconnect the battery, remove the control unit, create a repair order online and send the unit off well packed. Airbag24 checks it on the test bench, replaces defective components, erases the crash data and carries out a function test before your own unit is returned.

Disconnecting the battery before removal is a safety requirement. 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 89170-48490 get to Airbag24?

You send the unit to Airbag24 as a parcel, or you book a UPS collection for an extra charge. Airbag24 sends it back to you by UPS after the repair.

Enclose the printed repair order with the parcel. Pack the control unit so that it arrives shock-resistant.