Airbag control unit with part number 89170-53090

What does the airbag control unit 89170-53090 do?

For Lexus, the 89170-53090 is the central control unit of the restraint system (SRS). It evaluates the crash sensors, decides in a crash within milliseconds which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. Reported faults are shown via the airbag warning light.

This includes the continuous check of the ignition circuits, so that everything stands ready in an emergency. The decision is based on signals from the sensors, not on a simple switch.

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

Why does the control unit 89170-53090 fail?

Stored crash data is the most common cause in the 89170-53090, even when no airbag deployed in the accident. A normal diagnostic tool cannot remove the data. Added to this are aged components, cold solder joints, moisture and corrosion on plug connectors, and voltage spikes.

Crash data consists of measured values from the moment of impact. It remains stored even if the vehicle afterwards runs without any irregularity.

The other causes develop gradually: components age, connections are attacked by moisture, and voltage spikes arise, for example with a weak battery or jump-starting.

How can you tell that the 89170-53090 is defective?

A defect in the 89170-53090 is recognised by the airbag warning light in the instrument cluster, when it lights up permanently or intermittently. In addition there may be an error message in the instrument cluster, a lack of connection between the diagnostic tool and the control unit, or a fault memory that cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then fail to trigger.

The warning light is the signal you notice first in everyday life. It tells you a fault exists, but not which component is affected.

Write down an error message before you reset anything, so you can later trace what was displayed.

Which vehicles is the 89170-53090 fitted in?

Our details for Lexus assign this control unit. The 89170-53090 is fitted in these vehicles: Lexus IS XE20 (2005-2009) and XE20 Facelift (2010-2013).

The vehicles recorded for this part number are listed in the following overview.

• Lexus IS XE20 (2005-2009)
• Lexus IS XE20 Facelift (2010-2013)

Compare the part number on the label of the removed unit with this page, so that you have the right unit in front of you. Have the fault memory read out beforehand; 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 89170-53110, 89170-53480, 89170-53490, 89170-53540, 89170-53560, 89170-53570.

How does the repair of the 89170-53090 work?

You first have the fault memory read out and enclose the log. Then disconnect the battery, remove the 89170-53090, create a repair order online and send the unit in well packed.

Airbag24 checks the unit on the test bench, replaces defective components, deletes stored crash data and carries out a function test. For testing, repairing and checking, Airbag24 needs 3–4 working days.

Afterwards your own unit comes back to you. 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 89170-53090 get to Airbag24?

You send the 89170-53090 as a parcel or book a UPS collection for an extra charge; after repair Airbag24 sends it back to you by UPS.

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