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Glass breakage sensor

Glass breakage sensor


Glass breakage sensor

The sensor senses sound (microphone), such as a window being broken. It is integrated with the dome light in the roof (cabriolet: adjacent to the interior rearview mirror) and connected to the electronic control module as follows:


Anti-theft alarm via pin 7/signal and pin 5/ground

Anti-theft alarm with VSS via pin 7/signal and pin 13/ground

The separate ground input for the sensor in the anti-theft alarm without VSS has a filtering effect to avoid differences in potential between the electronic control module's main ground and the sensor's ground input.

When the theft alarm is armed and a window is broken, the sensor sends and analogue signal to the control module to set off the alarm. There is also a button beside the sensor for manual disconnection of the glass breakage sensor. When the disconnection button is pressed, disconnection happens through the control module sensing a change in the signal level.


Connection

The sensor is connected when the rest of the theft alarm is armed.




Manual disconnection

The sensor can be disconnected using the disconnection button as follows:


If the button is depressed when the alarm is not armed and the ignition is off. The sensor will then not be connected when the anti-theft alarm is later armed. The LED will flash at a rate of 1 flash/second for 10 seconds when the button is depressed. The LED will go on continuously (normal 10-second delay) if the alarm is armed before that.

The sensor can be reconnected, before the anti-theft alarm is armed, by turning the ignition switch to the "ON" position (+15) and then back again.

Otherwise, it is necessary to disarm the alarm and then arm it again so that the sensor will be connected with the rest of the alarm.


Automatic disconnection

The sensor is automatically disconnected in the following cases:


If the theft alarm is disarmed.

If the tailgate alone is disarmed/unlocked by the remote control or car key (US/CA).

If a door or the tailgate is open as the alarm is armed.

If voltage drops to < +8.5 V.


Cabriolet



Anti-Theft Alarm If the soft top is down, the glass breakage sensor should be disconnected manually with the disconnection button in order to avoid false alarms.

Anti-theft alarm with VSS The glass breakage sensor is disconnected automatically when the soft top is lowered and reconnected when it is raised.