Airbag control unit with part number 89170-11070

What does the airbag control unit 89170-11070 do?

The airbag control unit 89170-11070 coordinates the restraint system (SRS) of Lexus. It evaluates the crash sensors, determines within milliseconds which airbags and seatbelt pretensioners fire, and monitors the system continuously.

The decision to deploy is made on the basis of the measured values. If the unit detects a fault, it reports it via the airbag warning light so that the driver can see it.

After an accident, it secures the crash data and locks itself.

Why does the control unit 89170-11070 fail?

The most common cause is crash data stored in control unit 89170-11070 after an accident, even without a deployed airbag. A normal diagnostic tool cannot erase it. Aged electronics, cold solder joints, moisture and corrosion at plugs, and voltage spikes are also possible causes.

Such entries remain in the memory until they are removed during the repair. A diagnostic tool in normal operation cannot do this, so the warning stays on.

The other causes mainly concern the age and environment of the electronics. Over time, components age and solder joints lose their connection, and moisture attacks plug contacts. Voltage spikes, for example from a weak battery or after a jump-start, add further strain to the electronics.

How can you tell that the 89170-11070 is defective?

Typical signs are an airbag warning light in the instrument cluster that stays on permanently or intermittently, and error messages in the display. The diagnostic tool also fails to establish a connection to control unit 89170-11070, and the fault memory cannot be cleared.

These signs can occur individually or together:

• Airbag warning light stays on permanently or intermittently
• Error message in the instrument cluster
• No connection between the diagnostic tool and the control unit
• Fault memory cannot be cleared

As long as the fault persists, airbags and seatbelt pretensioners may not fire in an emergency. The warning light is a clear signal that must lead to a check.

Which vehicles is the 89170-11070 fitted in?

Control unit 89170-11070 is found in these vehicles from Lexus: Lexus LC URZ100 (from 2017). The assignment is based on the known deployments of this part number.

The following overview shows the recorded models and versions:

• Lexus LC URZ100 (from 2017)

Comparing the part number on the label of the removed unit with this page only shows whether it is the right unit. It says nothing about the condition. Have the fault memory read out beforehand, because only the result shows whether the control unit or a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 89170-11020, 89170-11140, 89970-50100.

How does the repair of the 89170-11070 work?

For safety reasons, a fixed sequence applies: first have the fault memory read out and enclose the log, then disconnect the battery and only after that remove control unit 89170-11070. Then create the repair order online and send the unit in well packed. At Airbag24, testing, repair and function testing usually take 3–4 working days.

Airbag24 checks the unit, replaces defective components, erases the stored crash data and carries out a function test. Afterwards, your unit is returned 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 89170-11070 get to Airbag24?

You can send control unit 89170-11070 in as a parcel or have it collected by UPS for an extra charge. Airbag24 returns the unit by UPS after the repair.

Enclose the printed repair order in the parcel. Pack the control unit so that it withstands transport undamaged.