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.
Start Control Module (SCU) (3/1): Notes
Type
Ignition switch: Electro mechanical switch.
Immobilizer: Transponder reader that reads off the Key's ID.
The immobilizer checks that the key is valid. If the key is not valid, the vehicle cannot be started.
Characteristic
The resistance between the control module's pins must be at least 100 kΩ for open circuit, and maximum 100 mΩ for closed circuit.
Other information
On all vehicles with an automatic gearbox, and vehicles on the American market, there is a solenoid in the ignition switch that prevents the key from being turned from position I to 0 if the correct conditions are not met.
Use the Manual With the Right Hardware
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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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