Airbag control unit with part number 89170-47770

What does the airbag control unit 89170-47770 do?

The airbag control unit 89170-47770 controls the restraint system (SRS) of Toyota. It processes the signals of the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners are triggered. After an accident, it locks itself.

During operation, the unit continuously monitors the trigger circuits and the sensors. If it detects a fault, it shows this via the airbag warning light in the instrument cluster. It also stores fault information that a diagnostic tool can read out.

Why does the control unit 89170-47770 fail?

The most common cause is crash data left in the memory after an accident, even if no airbag has triggered. A standard diagnostic tool cannot erase it. Further causes are aged components, dry solder joints, moisture, corrosion and voltage spikes.

Crash data arises regardless of whether an airbag has fired. Removing it is part of the repair, not of the diagnosis.

The other triggers at a glance:

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

How can you tell that the 89170-47770 is defective?

A defect shows up as an airbag warning light in the instrument cluster that lights up permanently or intermittently. In addition, there is an error message in the instrument cluster, no connection from the diagnostic tool to the control unit, and a fault memory that cannot be cleared.

The warning light makes it clear that something is wrong in the restraint system. In an emergency, airbags and seatbelt pretensioners may then not trigger.

Have the system checked promptly rather than ignoring the warning.

Which vehicles is the 89170-47770 fitted in?

The 89170-47770 is fitted in these vehicles: Toyota Prius IV XW50 (2015-2018) and IV XW50 Facelift (2018-2022).

The following overview shows the vehicles assigned to this part number.

• Toyota Prius IV XW50 (2015-2018)
• Toyota Prius IV XW50 Facelift (2018-2022)

Before removal, compare the part number on the label of the unit with this page; this ensures that it is the right unit. Whether the control unit itself is defective or a plug or cable is the cause only shows when the fault memory is read out. Have this done in advance.

For the same vehicles, we also repair control units with the part numbers 89170-47030, 89170-47611.

How does the repair of the 89170-47770 work?

First read out the fault memory, enclose the log, then disconnect the battery before removing the control unit. Afterwards, create a repair order online and pack the unit well before sending it in. Airbag24 checks it, replaces defective components, erases the crash data and tests the function; processing there usually takes 3–4 working days.

At the end, a function test takes place before your own unit is returned.

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 89170-47770 get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. Place the printed repair order in the parcel and pack the unit shock-proof. After the repair, Airbag24 returns it by UPS.

Sturdy packaging protects the electronics from knocks in transit.