Airbag control unit with part number 89170-48A50

What does the airbag control unit 89170-48A50 do?

The airbag control unit 89170-48A50 is the central control unit of the restraint system for Lexus. It processes the readings from the crash sensors, decides within milliseconds in an accident on airbags and seatbelt pretensioners, and checks the system continuously.

The airbag warning light in the instrument cluster displays faults as soon as the unit detects one. A glance is enough to see whether the system is reporting irregularities.

After an accident, the unit stores crash data and then locks itself. This can also happen in an accident in which no airbag was deployed.

Why does the control unit 89170-48A50 fail?

Stored crash data is the most common cause of failure of the 89170-48A50, even if no airbag has deployed. Aged components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes are also possible causes.

An ordinary diagnostic tool cannot remove this crash data, so it stays in the unit.

Aged electronics, damp plug connectors and voltage spikes, for example from a weak battery, also belong among the causes.

How can you tell that the 89170-48A50 is defective?

The airbag warning light in the instrument cluster indicates a defect in the 89170-48A50 by staying on permanently or intermittently. In addition, there is an error message in the instrument cluster, a diagnostic tool without a connection to the control unit, and a fault memory that cannot be erased.

The warning light lighting up is a clear signal, not a mere lamp question.

If the control unit is faulty, airbags and seatbelt pretensioners may fail to deploy in an emergency. For this reason, a prompt check of the fault memory is recommended.

Which vehicles is the 89170-48A50 fitted in?

The control unit 89170-48A50 is fitted in these vehicles: Lexus RX AL20 (2015-2019).

The following overview summarises the assigned models.

• Lexus RX AL20 (2015-2019)

Compare the part number on the label of the removed unit with this page. This only confirms that it is the right unit. Also have the fault memory read out, because only this log shows whether the control unit itself is defective or whether a connector 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 89170-48A50 work?

For the 89170-48A50, 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 pack the unit well.

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. Your own unit is then returned to you.

Processing at Airbag24 usually takes 3–4 working days, counted only for inspecting, repairing and testing. 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 89170-48A50 get to Airbag24?

You can send the control unit 89170-48A50 in as a parcel or have it collected by UPS for an extra charge. Airbag24 sends it back to you by UPS after the repair.

Place the printed repair order in the parcel and wrap the unit shockproof.