Airbag control unit with part number 89170-52A50

What does the airbag control unit 89170-52A50 do?

The airbag control unit 89170-52A50 processes the signals from the crash sensors at Toyota and decides within milliseconds in an accident whether airbags and seatbelt pretensioners are triggered. At the same time it monitors the entire restraint system (SRS) and reports faults.

Reported faults appear on the airbag warning light in the instrument cluster. After an accident the unit stores crash data and locks itself; this lock is only lifted by the repair.

Why does the control unit 89170-52A50 fail?

The most common cause is crash data from an accident, which remains stored in the unit even if no airbag has deployed. A conventional diagnostic tool cannot remove it. Other causes include ageing electronics, dry solder joints, moisture and voltage spikes.

Crash data is the most common cause because it burdens the unit regardless of whether airbags were triggered. It cannot be erased again by normal means.

The other causes relate to ageing of components, dry solder joints, and moisture and corrosion at plug connections. Voltage spikes, for example from a weak battery or a jump start, add to this.

How can you tell that the 89170-52A50 is defective?

The defect shows up as the airbag warning light, which lights up constantly or intermittently, and as fault messages in the instrument cluster. In addition, the diagnostic tool cannot connect to the control unit, and the fault memory cannot be cleared.

Typical signs are:

• airbag warning light on constantly or intermittently
• fault message in the instrument cluster
• no connection to the diagnostic tool
• fault memory cannot be cleared

In an emergency, airbags and seatbelt pretensioners may not be able to deploy. Please have the vehicle checked promptly.

Which vehicles is the 89170-52A50 fitted in?

The control unit 89170-52A50 is fitted in vehicles from Toyota: Toyota Yaris XP90 (2005-2009) and XP90 Facelift (2009-2011). You can check whether your vehicle is among them using the list on this page.

The following vehicles are stored:

• Toyota Yaris XP90 (2005-2009)
• Toyota Yaris XP90 Facelift (2009-2011)

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

For the same vehicles, we also repair control units with the part numbers 212986-105, 212986-110, 220749-101, 89170-0D170, 89170-0D230, 89170-0D440.

How does the repair of the 89170-52A50 work?

First have the fault memory read out and attach the log to the unit. Then disconnect the battery and only afterwards remove the control unit 89170-52A50. Next, create a repair order online and send the well-packed unit in.

Airbag24 checks the unit on the test bench, replaces defective components and erases stored crash data. This is followed by a function test, and then your own unit is returned to you.

Checking, repairing and testing 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 89170-52A50 get to Airbag24?

You send the control unit 89170-52A50 as a parcel, or you book a UPS collection for an extra charge. Airbag24 returns the repaired unit to you by UPS.

Put the printed repair order in the parcel, and pack the unit shock-proof.