Airbag control unit with part number 89170-48A00

What does the airbag control unit 89170-48A00 do?

The airbag control unit 89170-48A00 is the central control unit of the restraint system for Lexus. It evaluates the crash sensors, decides on airbags and seatbelt pretensioners within milliseconds in a crash, and signals faults via the airbag warning light.

Several sensor values are used together to make this decision. Outside an accident, the unit monitors the components of the system continuously, so that the system is ready in an emergency.

After an accident it creates crash data and locks itself. The airbag warning light in the instrument cluster informs you about the state of the system.

Why does the control unit 89170-48A00 fail?

For the 89170-48A00, the most common cause is the storage of crash data after an accident, even if no airbag has deployed. Other causes include aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes from the vehicle electrical system.

A standard diagnostic tool cannot remove this crash data. The fault therefore remains, even if everything else appears normal. At Airbag24 the crash data is cleared during the repair.

Aged components, cold solder joints and moisture at plug connections affect the electronics over a longer period. Voltage spikes, for example when starting with a weak battery or when jump-starting, add further strain. Only the evaluation of the fault memory shows which cause is present.

How can you tell that the 89170-48A00 is defective?

On the 89170-48A00, a defect is indicated by an airbag warning light in the instrument cluster that stays on permanently or intermittently, by an error message, by a diagnostic tool without connection to the control unit, or by a fault memory that cannot be cleared.

The airbag warning light is the most important indication, because it shows a fault in the system. If an error message remains in the instrument cluster, have the finding clarified promptly.

If the system cannot fully check a fault, airbags and seatbelt pretensioners may fail to deploy in an emergency.

Which vehicles is the 89170-48A00 fitted in?

The airbag control unit 89170-48A00 is fitted in these vehicles: Lexus RX AL20 (2015-2019).

The list shows the vehicles that are assigned to this part number.

• Lexus RX AL20 (2015-2019)

Comparing the part number on the label of the removed unit with this page only confirms that you have the correct unit. Also have the fault memory read out before you remove the unit: only this 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 89170-48A00 work?

First have the fault memory of the 89170-48A00 read out and enclose the log, then disconnect the battery and remove the 89170-48A00. At Airbag24, inspection, repair and testing usually take 3–4 working days.

Afterwards create a repair order online and pack the unit well for sending. Only then does the processing begin. At the test bench, Airbag24 replaces defective components, clears the crash data and carries out a function test.

Your own unit is then returned to you. 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 89170-48A00 get to Airbag24?

You send the control unit 89170-48A00 in as a package, or book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

The printed repair order goes into the package, and the unit is packed shock-proof.