With Code 551a
Location Of Components - Sedan:
Location Of Components - Wagon:
The interior motion sensor is a supplement to the present anti- theft alarm (ATA) and serves for additional protection e.g. when one of the side windows is broken.
The interior motion sensor becomes active approximately 60 s after locking the vehicle.
The passenger compartment is protected by infrared light rays.
Location Of Components:
On the T-models glass breakage sensors (B39, B39/1) are vapor-coated onto the insides of the rear side windows. The rear window is protected by the rear window defroster element (R1) on model 210.2
On models 202.07/08/18 a glass breakage sensor (B39/4) is vapor-coated onto the inside of the rear window.
Scope Of Protection, Infrared Interior Motion Sensor:
The following modifications have been made on the infrared interior motion sensor in comparison to the previously familiar system:
- Infrared interior motion sensor control module eliminated
- Evaluation in associated transmitter and receiver module
- New transmitter and receiver modules
- Optical components permanently integrated into transmitter and receiver module
If an attempt is made to break into the car, e.g. a side window is broken, the reflection of the infrared rays is changed.
This change in reflection is fed to an A/D converter by the infrared transmitters and receivers (interior protection system) (A26/4, A26/5) individually via filter, amplifier, rectifier and integrator. If during evaluation a coincidence with stored break-in patterns is detected, the anti-theft alarm (ATA) control module (N26) receives a signal to trip from the affected infrared transmitter and receiver (interior protection system) (IR) (A26/4, A26/5).
NOTE: On model 210 the anti-theft alarm (ATA) control module is integrated into the pneumatic system equipment (PSE) multi-function control module (A37).
The ambient light is measured continuously for adaptation of the signal.
Swinging of an item such as a jacket hanging on a coat hook, is recognized electronically and ignored so that the alarm is not tripped.
Procedures following system activation
- Initial measuring procedure
- Formation of reference value
- Sleep mode
Break-in attempt
- Wake mode
- Comparison with stored patterns
- Alarm actuation