Activating and Deactivating Alarm System

Activating And Deactivating Alarm System

The alarm system is activated by a ground signal at the activation input or by an activation signal from the hand-held transmitter.

The activation of the system is ignored if pin 86 S, pin 15 or a valid transponder key is recognised.

If for some reason it is not possible to lock the central locking system with a single locking command, the alarm system is not activated. Activation of the alarm system cannot be achieved until the central locking system is locked (manually if necessary) and a new activation command is issued or only locking is performed three times in quick succession. The interval between two locking operations must not be more than 1 second in this case. If the system is activated by this emergency function, the central locking system is locked without checking whether it can be completely locked.

The system saves the type of activation in a status memory. If an alarm is triggered, this information is written to the alarm memory together with the alarm coding.

When the alarm system is activated, the inactive level of all inputs is checked for an inactive period of 10 seconds. Only inputs which are inactive for the entire inactive period can trigger the alarm after the end of the inactive period. All other inputs are blocked for alarm triggering for as long as they are in the active state. If the inactive state occurs at blocked inputs, the inactive period is started for them individually. All inputs which remain in the inactive state during the inactive period are then included in the alarm evaluation.

The inactive period commences immediately after activation if:
- it is apparent that the central locking system is locked or if locking occurred three times in succession.
- the 'Activate' signal is no longer present. (A second activation command for cancelling the anti-theft protection restarts the inactive period).

In the case of an active signal at the inputs pin 86 S, pin 15 or if a valid transponder key is recognised, no activation is possible. If one of these inputs is active at the time of locking, control of the central locking system does not take place. The central locking system is opened if one of these inputs becomes active during the inactive period, since in this case the alarm system is also deactivated.

If, when the vehicle is locked, a door is unlocked after the 10 second inactive period, this is immediately actuated to 'Closed'. An alarm is triggered at the same time. If, when the vehicle is locked, a door is unlocked from the inside during the inactive period, the central locking system is unlocked and the alarm system is deactivated. (Protection against unintentional locking/activation).

If, within 15 seconds of switching on the 'External Electronics' output, movements in the vehicle are detected by the passenger compartment monitoring system, the central locking system is changed to the locked position and the alarm system is deactivated.

After the inactive period, the 'External Electronics' output is switched on if the alarm-triggering inputs, such as doors, convertible top, convertible top compartment cover, front luggage compartment and rear engine compartment, were inactive for the entire inactive period. If one of these inputs is active, the 'External Electronics' output is not switched on until this input becomes inactive and remains in this state for at least 10 seconds. The switched-on 'External Electronics' output cannot be deactivated again by activating one of the above inputs. The output is switched off when deactivation takes place.

If, within a period of less than 1 second after the first activation pulse, a second activation command is issued, the 'External Electronics' output is not switched on for one activation cycle. In this case, the central locking system is not secured, but only locked. This is acknowledged by signal 1 at the alarm horn and at the direction indicator light output, as well as during the deactivation period by the display type 3 at the alarm readiness display output and at the 'Door locked' display output. An opening command deletes the switch-off command.

If activation occurs by way of the emergency function (locking 3 times quickly), the 'External Electronics' output is not switched on for this activation cycle. This is acknowledged by signal 1 at the alarm horn and direction indicator light outputs, as well as by display type 2 at the alarm readiness display output. A deactivation command deletes this command.

If pin 86 S, pin 15 or a valid transponder key is recognised during the deactivation period, the alarm system is deactivated (protection against unintentional activation). The central locking system is opened in this case.

A system self-test is carried out upon activation. The result of this test is acknowledged via the alarm readiness light and the 'Door locked' display and can be called up from the status memory via the diagnosis function. Equipment faults are written to the fault memory. Faults are indicated at the alarm horn and direction indicator light outputs by signal 2.

The alarm system is deactivated by a ground signal at the 'Deactivate' input or by a deactivation signal from the hand-held transmitter. If a valid transponder key is recognised, the alarm system is also deactivated.