Airbag control unit with part number 89170-24280

What does the airbag control unit 89170-24280 do?

The airbag control unit 89170-24280 is the central control unit of the restraint system (SRS) for Lexus. It evaluates the signals from the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners are triggered. In addition, it monitors the system continuously and indicates faults via the airbag warning light.

During driving, the control unit checks whether sensors, wiring and trigger circuits deliver plausible values. If a value deviates, it creates an entry in the fault memory, from which the cause can be read later.

After an accident, the control unit stores crash data and then locks itself. This also applies when no airbag has deployed.

Why does the control unit 89170-24280 fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed. A normal diagnostic tool cannot erase it. Other causes are 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.

That crash data is stored in the unit even though no airbag has deployed cannot be seen from outside the vehicle. A diagnostic tool can reach the data, but it cannot remove it.

The other causes develop over a longer period. Electronic components age, solder joints can give way with temperature changes, and moisture or corrosion worsen the contact at plug connections.

How can you tell that the 89170-24280 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, a fault message appears in the instrument cluster, the diagnostic tool receives no connection to the control unit, and the fault memory cannot be cleared. In such cases, airbags and seatbelt pretensioners may possibly not trigger in an emergency.

The warning light is the clearest indication. It shows that the system has detected a fault, and it must not be ignored, even if it goes out again in between.

The message in the instrument cluster names the problem, not its cause. If the diagnostic tool also has no connection, you should have the finding checked promptly, because the control unit itself may be affected.

Which vehicles is the 89170-24280 fitted in?

The 89170-24280 is fitted in these vehicles: Lexus RC ASC10 (2015-2018) and ASC10 Facelift (from 2018).

The following list shows the vehicles for which this part number is on file with Airbag24.

• Lexus RC ASC10 (2015-2018)
• Lexus RC ASC10 Facelift (from 2018)

Compare the part number on the label of the removed unit with this page. This only ensures that you have the correct unit. Also have the fault memory read out, because only the log 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 89170-24170, 89170-24300, 89170-24320, 89170-24340, 89170-78010.

How does the repair of the 89170-24280 work?

First have the fault memory read out and enclose the log with the unit. Then disconnect the battery and only afterwards remove the control unit. Processing at Airbag24 usually takes 3–4 working days.

Next, create a repair order online and pack the unit carefully for dispatch. Airbag24 checks it on the test bench, replaces defective components, erases the stored crash data and carries out a function test. Afterwards your own unit is returned to you.

This sequence is for your safety. The 3–4 working days refer solely to checking, repairing and testing 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 89170-24280 get to Airbag24?

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

Put the printed repair order into the parcel and pack the unit shock-proof.