Door switches
The door switches which control the interior lighting are also the sensors for the doors in the alarm system. The four switches are mounted in the frame for the door concerned and are activated when the door is opened or closed.
The door switches are connected to the following pins of the TWICE control module:
Driver's door
|
pin no. 61
|
Passenger door
|
pin no. 60
|
Rear door, left
|
pin no. 12
|
Rear door, right
|
pin no. 36
|
A pulse width-modulated (approx. 3.5%) voltage is supplied continuously from the control module via a 1 kohm pull-up in TWICE to the switch concerned. From this voltage, the control module can detect whether a door is opened when the alarm is armed by testing the voltage at the input concerned.