Airbag control unit with part number 89170-04540

What does the airbag control unit 89170-04540 do?

The airbag control unit 89170-04540 processes the measurements from the crash sensors in the restraint system (SRS) of Toyota. In an accident it decides within milliseconds which airbags and seatbelt pretensioners are triggered, and monitors the system continuously.

If the system reports a fault, the airbag warning light in the instrument cluster comes on. In this way, drivers learn of a malfunction.

After an accident the unit stores crash data and locks itself.

Why does the control unit 89170-04540 fail?

The most common cause is crash data from an accident, even if no airbag was triggered. A normal diagnostic tool does not delete it. Other causes are ageing electronics, cold solder joints, moisture or corrosion at plug connections, and voltage spikes.

Besides the crash data, these causes come into consideration:

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

The crash data stays stored in the unit, and a normal diagnostic tool cannot remove it. Which cause applies in the individual case is shown only by the fault memory.

How can you tell that the 89170-04540 is defective?

A defect shows up through the airbag warning light in the instrument cluster, which stays on continuously or intermittently, through a fault message in the instrument cluster, through no connection to the diagnostic tool, and through a fault memory that cannot be cleared.

• Airbag warning light in the instrument cluster stays on continuously or intermittently
• Fault message in the instrument cluster
• Diagnostic tool gets no connection to the control unit
• Fault memory cannot be cleared

A lit warning light means the system has detected a fault. It cannot tell you whether the fault lies in the control unit or in the wiring.

During the fault, airbags and seatbelt pretensioners may fail to deploy in an emergency. Have the system checked promptly.

Which vehicles is the 89170-04540 fitted in?

The control unit 89170-04540 is fitted in the following vehicles: Toyota Tacoma N200 (2004-2015). The list helps narrow things down, but a check of the unit is still required.

Below you will find the vehicles we have on record for this part number.

• Toyota Tacoma N200 (2004-2015)

Compare the part number on the label of your removed unit with this page. This only confirms the identity of the unit. Have the fault memory read out beforehand, 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 89170-04420, 89170-04570, 89170-04600, 89170-04650.

How does the repair of the 89170-04540 work?

Have the fault memory read out and attach the log. Disconnect the battery and then remove the control unit. Create an online repair order and pack the unit well before sending it. Airbag24 usually schedules 3–4 working days for processing.

Airbag24 first checks the unit on the test bench, replaces defective components, deletes stored crash data and carries out a function test. Afterwards your own unit goes back to the sender.

The steps at the vehicle follow a fixed sequence, because safety comes first.

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 89170-04540 get to Airbag24?

The shipment runs either as a parcel you send yourself or via a UPS collection, which can be booked for an extra charge. The return after the repair goes by UPS.

Enclose the printed repair order with the parcel. Pack the unit shock-proof so that it arrives undamaged.