Airbag control unit with part number 89170-47A20

What does the airbag control unit 89170-47A20 do?

The control unit 89170-47A20 ensures in the restraint system (SRS) of Toyota that airbags and seatbelt pretensioners react correctly in a crash. To do this it processes the signals from the crash sensors and monitors the system constantly. It shows detected faults via the airbag warning light.

The sensors measure how the vehicle accelerates or decelerates. From these values the unit calculates whether an impact requires triggering.

If an accident is detected, the unit stores crash data and locks itself. This reaction is prescribed.

Why does the control unit 89170-47A20 fail?

The most common cause with the 89170-47A20 is crash data from an earlier accident, even if no airbag fired. A normal diagnostic tool cannot remove this data. Aged electronics, cold solder joints, moisture and corrosion, as well as voltage spikes, also come into question.

The crash data remain in the memory even when the vehicle then drives completely normally again.

Further causes can be summarised briefly:

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

How can you tell that the 89170-47A20 is defective?

A defect on the 89170-47A20 shows itself when the airbag warning light in the instrument cluster stays on permanently or intermittently, an error message appears in the instrument cluster, the diagnostic tool cannot establish a connection to the control unit, or the fault memory cannot be cleared.

Each of these signs justifies a check. The warning light shows the state of the system most directly.

In an emergency, airbags and seatbelt pretensioners may possibly not trigger as long as such a finding exists. A prompt check is therefore the right next step.

Which vehicles is the 89170-47A20 fitted in?

The control unit 89170-47A20 is fitted in these vehicles: Toyota Prius V XW60 (from 2022).

Here the assignment comes in list form:

• Toyota Prius V XW60 (from 2022)

Comparing the part number on the label of the removed unit with this page ensures that you have the right unit in front of you. Have the fault memory read out beforehand, because only the log clarifies whether the control unit is defective or a cable or connector is the cause.

For the same vehicles, we also repair control units with the part numbers 89170-47030, 89170-47860.

How does the repair of the 89170-47A20 work?

For the 89170-47A20 you first have the fault memory read out and attach the log. Then you disconnect the battery and only afterwards remove the control unit. Next you create the repair order online and send in the unit well packed.

Airbag24 checks the unit on the test bench, repairs defective components, deletes the stored crash data and carries out a function test. After that your own unit is returned to you.

Processing at Airbag24 usually takes 3–4 working days. 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 89170-47A20 get to Airbag24?

You send the 89170-47A20 as a parcel to Airbag24, or you book a UPS collection for an extra charge. After the repair Airbag24 sends the unit back by UPS. You put the printed repair order into the parcel and pack the unit shock-proof.

A firm box with padding is enough to keep everything inside from shifting.