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.
Movement sensor
The Mass Movement Sensor detects movement in the passenger compartment using radio waves at 2.450 GHz. The Doppler effect principle is used to determine if the frequency of the received microwave has been modified in comparison to the transmitted microwave. Any change in frequency is interpreted as a movement in the car. When movement is detected, a trigger signal is sent to the upper electronic module which activates the alarm.
The movement sensor is located in the headlining in the center of the car. This allows the sensor to cover as large an area as possible.
There are diagnostics for the movement sensor.
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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