Airbag control unit with part number 89170-BZ700

What does the airbag control unit 89170-BZ700 do?

The airbag control unit 89170-BZ700 controls the restraint system (SRS) of Toyota. It checks the signals of the crash sensors, decides in a crash within milliseconds on the triggering of airbags and seatbelt pretensioners, and monitors the entire system. After a crash it stores crash data and locks itself.

Detected faults are reported by the unit via the airbag warning light. The control unit ensures that sensors, airbags and seatbelt pretensioners work together.

The check runs constantly in the background, even when the vehicle is standing still.

Why does the control unit 89170-BZ700 fail?

The most common cause is crash data stored after an accident, even if no airbag was triggered; a normal diagnostic tool does not erase it. Other causes include aged components, cold solder joints, moisture and corrosion at plug connectors, and voltage peaks.

Crash data remains in the memory after it has been read out. Airbag24 erases it during the repair.

In detail, the following points are relevant:

• aged electronics
• cold solder joints
• moisture and corrosion at plug connectors
• voltage peaks, for example from a weak battery or a jump start

How can you tell that the 89170-BZ700 is defective?

The airbag warning light in the instrument cluster lights up constantly or intermittently, a fault message appears in the instrument cluster, the diagnostic tool cannot find the control unit, or the fault memory cannot be cleared. In that case the airbags and seatbelt pretensioners may fail to trigger in an emergency.

The warning light should go out after the ignition is switched on. If it stays on, there is a fault in the system that you should have checked.

A diagnostic tool that cannot establish a connection to the control unit is also a sign that something is wrong. Then have the system checked promptly.

Which vehicles is the 89170-BZ700 fitted in?

The airbag control unit 89170-BZ700 is fitted in these vehicles: Toyota Avanza F650 Facelift (2015-2023).

The following vehicles are on record:

• Toyota Avanza F650 Facelift (2015-2023)

Compare the part number on the label of the removed unit with this page. This only confirms that you have the correct unit in front of you. Also have the fault memory read out beforehand, because only the log shows whether the control unit is defective or whether a plug or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 17952812-928112, 17952815-928143, 89170-BZ440.

How does the repair of the 89170-BZ700 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit. Next you create a repair order online and send the unit in well packed. Airbag24 checks it, replaces defective components, erases crash data, tests the function and returns your own unit.

The order serves safety: as long as the battery is connected, no work may be carried out on the airbag system.

At Airbag24 processing usually takes 3–4 working days. Checking, repair and function test take place during this time. 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-BZ700 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 by UPS; the printed repair order goes into the parcel.

The control unit should be packed shock-resistant so that it survives transport.