Airbag control unit with part number 89170-48420

What does the airbag control unit 89170-48420 do?

The airbag control unit 89170-48420 carries out all triggering of the restraint system (SRS) in the Toyota. It evaluates the crash sensors and, in an accident, decides within milliseconds on airbags and seatbelt pretensioners.

The system is monitored continuously. If the unit detects a fault, it reports it via the airbag warning light in the instrument cluster.

After an accident it stores crash data and locks itself. The lock is lifted only by the repair.

Why does the control unit 89170-48420 fail?

The most common cause of failures on the 89170-48420 is crash data remaining in memory after an accident, even without an airbag deployment. Electronics, connection and power supply problems can also contribute.

Crash data cannot be removed with an ordinary diagnostic tool. Airbag24 erases it during the repair.

Other possible causes are:

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

How can you tell that the 89170-48420 is defective?

You can recognise a defect on the 89170-48420 by the airbag warning light, an error message in the instrument cluster, or the diagnostic tool being unable to connect to the control unit. The fault memory also cannot be cleared.

The typical signs are:

• airbag warning light on permanently or intermittently
• error message in the instrument cluster
• diagnostic tool without connection to the control unit
• fault memory that cannot be cleared

In an emergency, airbags and seatbelt pretensioners may fail to deploy in the event of such a finding. The warning exists precisely for this purpose and requires a check.

Which vehicles is the 89170-48420 fitted in?

The control unit 89170-48420 is fitted in these vehicles: Toyota Highlander XU40 (2007-2013). This applies to the stated part number.

The list of stored vehicles follows here:

• Toyota Highlander XU40 (2007-2013)

First compare the part number on the label of the removed unit with this page; this shows you have the right unit. Whether the control unit is defective or a plug or cable is the cause is decided only by the fault memory, which you have read out before removal.

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

How does the repair of the 89170-48420 work?

First have the fault memory read out and enclose the log with the unit. Then disconnect the battery and remove the 89170-48420.

Afterwards you create a repair order online and send in the well-packed unit.

Airbag24 tests the unit on the test bench, replaces defective components, erases the crash data and carries out a function test. The unit then returns to you.

Processing at Airbag24 usually takes 3–4 working days, covering testing, repairing and checking only. 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 89170-48420 get to Airbag24?

Either you send the 89170-48420 to Airbag24 as a parcel, or you book a UPS collection for an extra charge. The return of the repaired unit is made by UPS.

The printed repair order goes into the parcel. Pack the control unit shock-proof.