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Glass Breakage Sensor






The sensor senses sound (microphone), such as a window being broken. It is integrated with the interior lighting lamp in the roof and connected to the 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 version 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.

If a window is broken while the anti-theft alarm is armed, the sensor sends an analogue signal to the electronic control module so that the alarm will be set off. The sensor also has a button for manual disconnection of the glass breakage sensor. When this button is pressed, the electronic control module senses a change in the signal level and the sensor is disconnected.







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 pressed when the theft alarm is not armed and the ignition is off, the sensor will not then be connected when the theft alarm is armed. When the button is pressed, the LED flashes once every second for 10 seconds. If the theft alarm is armed before this, the LED goes to being lit continuously (normal 10 seconds delay).
- The sensor can be reconnected (before the anti-theft alarm is armed) by turning the ignition switch to the ON position (+15).
- 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.
- If a door or the tailgate is open on arming the alarm.
- If the voltage drops to lower than +8.5 V.