Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Immobilizer Antenna Unit (IAU)
The Immobilizer Antenna Unit (IAU) and its connected starter button and key switch are used by the driver to start the vehicle.
The starter button supplies the Engine Control Module (ECM) with start signals through a directly connected cable.
For more information about the components and signals, see (Immobilizer/Start inhibition) and CENTRAL ELECTRONIC MODULE (CEM) .
Also see: FUNCTION .
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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