Airbag control unit with part number 89170-42850

What does the airbag control unit 89170-42850 do?

The airbag control unit 89170-42850 forms the control of the restraint system of Toyota. It processes the signals from the crash sensors, determines in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously.

While driving it checks connections and components. If something fails, this is recorded in the fault memory and indicated via the airbag warning light.

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

Why does the control unit 89170-42850 fail?

The most common cause is crash data stored after an accident, which cannot be deleted with a normal diagnostic tool. Aged components, cold solder joints, moisture and corrosion, as well as voltage spikes, can also cause failure.

The car may drive normally again afterwards, but the crash data remains in the unit and cannot be removed by normal means.

• aged electronic components
• cold solder joints
• moisture at plug connections
• corrosion on contacts
• voltage spikes, for example from a weak battery or jump-starting

Airbag24 deletes the crash data during the repair.

How can you tell that the 89170-42850 is defective?

The airbag warning light in the instrument cluster indicates a defect in the 89170-42850 when it is on permanently or intermittently. An error message in the instrument cluster, a missing connection to the diagnostic tool and a fault memory that cannot be cleared are also signs of this.

The warning light comes on as soon as the system detects a fault, and thus reports the state of the restraint system. In an emergency airbags and seatbelt pretensioners may not trigger, so have the system checked promptly.

Whether the control unit is actually defective is shown only by reading out the fault memory.

Which vehicles is the 89170-42850 fitted in?

The information refers to Toyota. The airbag control unit 89170-42850 is fitted in these vehicles: Toyota RAV4 XA50 (from 2018).

This overview lists the vehicles recorded for this part number:

• Toyota RAV4 XA50 (from 2018)

Compare the part number on the label of the removed unit with this page; this only confirms that it is the correct unit. Have the fault memory read out beforehand as well, since only that 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 150800-4431, 152100-0262, 152100-4560, 89170-0R070, 89170-0R090, 89170-0R091.

How does the repair of the 89170-42850 work?

In the repair of the 89170-42850, have the fault memory read out and the log enclosed before you disconnect the battery and remove the control unit. Checking, repairing and testing take 3–4 working days as a rule at Airbag24.

Then you create a repair order online and pack the unit well before sending it. Airbag24 checks the unit on the test bench, replaces defective components, deletes stored crash data and carries out a function test. Afterwards your own unit is 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 89170-42850 get to Airbag24?

You send the control unit 89170-42850 as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends it back by UPS.

Enclose the printed repair order in the parcel and pack the control unit shockproof.