Airbag control unit with part number 89170-48350

What does the airbag control unit 89170-48350 do?

The airbag control unit 89170-48350 forms the central control unit of the restraint system (SRS) in Toyota. It evaluates the signals from the crash sensors and, in an emergency, decides within milliseconds which airbags and seatbelt pretensioners are triggered. It also monitors the entire system continuously and reports faults via the airbag warning light.

After an accident, the unit stores crash data and locks itself. While locked, this goes unnoticed in normal driving.

In the background, the control logic keeps working quietly. It saves detected faults in the fault memory, which a workshop can read out with a diagnostic tool.

Why does the control unit 89170-48350 fail?

With the 89170-48350, the most frequent cause is crash data stored after an accident, even if no airbag has deployed; a normal diagnostic tool cannot erase it. Ageing components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes are also possible causes.

The crash data stays in the unit until Airbag24 deletes it during the repair. The fact that the airbags did not deploy makes no difference to this.

Other triggers are:

• ageing electronic components
• cold solder joints on the circuit board
• moisture and corrosion at plug connectors
• voltage spikes, for example from a weak battery or a jump start

How can you tell that the 89170-48350 is defective?

A defect in the 89170-48350 shows up as the airbag warning light in the instrument cluster staying on permanently or intermittently, and as a fault message in the instrument cluster. In addition, the diagnostic tool cannot establish a connection to the control unit, and the fault memory cannot be erased. In this case, the airbags and seatbelt pretensioners may not be able to deploy in an emergency.

These signs point to a defect:

• Airbag warning light on permanently or intermittently
• Fault message in the instrument cluster
• Diagnostic tool without a connection to the control unit
• Fault memory cannot be erased

If the warning light is on, have the system checked promptly. The light is there to make the defect visible, so take the indication seriously.

Which vehicles is the 89170-48350 fitted in?

The control unit 89170-48350 is fitted in these vehicles: Toyota Highlander XU40 (2007-2013).

The following list shows the assigned models.

• Toyota Highlander XU40 (2007-2013)

Compare the part number on the label of the removed unit with this page; this only confirms that you have the right unit. Also have the fault memory read out before removal, because only that shows whether the control unit itself is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 89170-48090, 89170-48240.

How does the repair of the 89170-48350 work?

For the 89170-48350, first have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit. Next, create the repair order online and send the unit off well packed. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, deletes stored crash data and carries out a function test. The unit then goes back to you. This period relates solely to checking, repairing and testing at Airbag24, not to your steps or the shipping.

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 89170-48350 get to Airbag24?

You send the control unit 89170-48350 as a parcel, or book a UPS collection for an extra charge. After the repair, Airbag24 sends it back by UPS.

Place the printed repair order in the parcel, and pack the unit shock-proof.