Airbag control unit with part number 89170-30700

What does the airbag control unit 89170-30700 do?

The airbag control unit 89170-30700 coordinates the restraint system (SRS) in the vehicle from Lexus. It processes the data from the crash sensors, decides within milliseconds in an accident whether airbags and seatbelt pretensioners are triggered, and monitors the entire system. After an accident it stores crash data and locks itself.

In everyday use, the unit works unnoticed in the background. If a fault occurs in the system, the airbag warning light in the instrument cluster shows it.

The stored crash data remain in the control unit.

Why does the control unit 89170-30700 fail?

Most often the cause lies in crash data stored after an accident, even if no airbag was triggered; a normal diagnostic tool cannot erase them. Other causes are ageing electronic components, cold solder joints, moisture and corrosion on plug connections, and voltage spikes, for example from a weak battery or after a jump-start.

The memory holds the crash data, and an ordinary diagnostic tool cannot remove this entry. It follows that the fault persists even without visible damage to the airbags.

The other causes concern the electronics and their connections. Electronic components lose reliability, solder joints can go cold, and moisture and corrosion attack plug connections.

Voltage spikes, for example from a weak battery or after a jump-start, place additional strain on the circuit.

How can you tell that the 89170-30700 is defective?

A defect shows up as an airbag warning light that stays on permanently or intermittently, as an error message in the instrument cluster, as a lack of connection to the diagnostic tool, or as a fault memory that cannot be cleared. In an emergency, the airbags and seatbelt pretensioners may then fail to trigger.

The warning light is the most important sign you will encounter in everyday driving. If it stays on permanently or flickers now and then, have the vehicle examined.

An error message in the instrument cluster is just as much a sign as a diagnostic tool that makes no contact with the control unit. A fault memory that stays full even after an attempt to erase it also points to a fault.

Which vehicles is the 89170-30700 fitted in?

The 89170-30700 is fitted in these vehicles: Lexus GS S190 Facelift (2009-2011) and S190 (2005-2009).

The models with this part number are listed here:

• Lexus GS S190 Facelift (2009-2011)
• Lexus GS S190 (2005-2009)

Comparing the part number on the label of the removed unit with this page confirms the right unit. This comparison shows nothing more. Whether the control unit is defective or a plug or cable is the cause is determined only by the fault memory, which you have read out before removal.

For the same vehicles, we also repair control units with the part numbers 89170-30B30, 8917030630.

How does the repair of the 89170-30700 work?

The process begins with reading out the fault memory, with the log enclosed; only then do you disconnect the battery and remove the control unit 89170-30700. Create the repair order online before you send in the well-packed unit. Airbag24 examines it on the test bench, rectifies the defects, erases stored crash data and tests the function, after which your own unit goes back.

The sequence is mandatory for safety reasons; there is no way around it.

Processing at Airbag24 usually takes 3–4 working days, counted exclusively for checking, repairing and testing.

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 89170-30700 get to Airbag24?

You send the control unit in as a parcel, or you book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

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