The immobilizer, central locking system, convertible top comfort control, radio remote control and monitoring of the vehicle interior functions are integrated in the alarm system.
The alarm system monitors the vehicle's outer panels by way of contact switches on the lids and in the doors. Attempted break-ins should be recognized and indicated by audible and visual signals.
The alarm horn, direction indicator lights and interior lights are activated to issue the alarm.
The system can be extended by connecting additional sensors (glass breakage sensor, tilt sensor).
The central locking system provides for three dif-
1. If the lock is activated once, the so-called "Safe locking- door secured" function is acti-
The doors can be opened only with the key, but not with the inside door handles.
2. If the door lock is activated twice within 1 second, the vehicle is not accessible from the outside, but can be unlocked via the inside door
3. The possibility of activating the door lock three times represents an emergency function. If the functional capability of the overall system is impaired because, for example, one door cannot be closed, it is possible in this way to still activate the other security func-
Point 1 is activated when the system is operated via the radio remote control. The position of the doors is checked by limit
Controlling the interior lights
The interior lights are not controlled directly by the door contacts. The interior lights are switched on:
1. When the doors are unlocked.
2. When the doors are opened.
The lighting stays on for approx. 30 seconds.
The interior lights are switched off (doors closed):
1. When the ignition is switched on.
2. When the doors are locked.
The interior lights are switched on and off dimmed.
If the convertible top is opened or closed, the convertible top control unit output and then (with a 200 ms delay) the comfort opening or comfort closing output are activated.
If the vehicle is locked up, some loads are disconnected from the supply voltage in order to conserve the battery. The load disconnection output is switched off after approx. 10 minutes for this purpose.
The loads are switched on by switching on terminal 86 S (buzzer contact), terminal 15 or by recognition of a valid transponder key.
The function depends on programmed national variant.
The output is controlled when terminal 15 is switched on or if a door is open.
The output is controlled if terminal 15 is switched on and also remains switched on after terminal 15 is switched off, until a door is opened. The output is switched off no later than when the vehicle is locked.
After the operating voltage is switched on, the system is set to the operating state which it was in before the supply voltage was switched off.
For this purpose, all necessary operating parameters are stored in a permanent memory. If the system was disconnected from the supply in the armed state, this is entered as a fault in the status memory. The same applies if the system is disconnected from the supply voltage during
Activating and deactivating
The system is activated by a ground signal at the activation input or by an activation signal
The activation of the system is ignored if terminal 86 S, terminal 15 or a valid transponder key
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 (if necessary manually) 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 into 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 if it is apparent that the central locking system is locked or if locking occurred three times in succession and if the signal "Activate" is no longer present. (A second activation command for cancelling the anti-theft protection restarts the inactive
In the case of an active signal at the inputs terminal 86 S, terminal 15 or if a valid transponder key is recognized, 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 expiry of the 10 second inactive period, this is immediately controlled in the direction "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 after switching-on of the output External Electronics, movements in the vehicle are detected by the passenger compartment monitor, the central locking system is moved to the locked position and the alarm system is deactivated.
After expiry of the inactive period, the output "External Electronics" is switched on if the alarm-triggering inputs for the doors, convertible top, convertible top compartment cover, front luggage compartment and rear luggage compartment were inactive for the entire inactive period. If one of these inputs is active, the output "External Electronics" is not switched on until this input becomes inactive and remains in this state for at least 10 seconds. The switched-on output "External Electronics" 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 output "External Electronics" 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 display output "Door locked". An opening command deletes the switch-off command.
If activation occurs by way of the emergency function (locking 3 times quickly), the output "External Electronics" is not switched on for this activation cycle. This is acknowledged by signal 1 at the alarm horn and direction indicator light output, as well as by display type 2 at the alarm readiness display output. A deactivation command deletes this command.
If terminal 86 S, terminal 15 or a valid transponder key is recognized 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 display "Door locked" and can be called up from the status memory via the diagnosis function. Equipment faults are written into 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 input "Deactivate" or by a deactivation signal from the remote control. If a valid transponder key is recognized, the alarm system is also deactivated.
The operating state of the central locking system is fed back via the output "Door locked" and by corresponding activation of the interior light (signals 1 to 3). The operating state of the alarm system is also indicated during the inactive period by the alarm readiness display (display types 1 to 6) and exclusively by the alarm readiness display following expiry of the inactive period. Displayed system faults are always current faults. Previous system faults entered in the status memory have no influence on the function display.
Display type 1 (normal flashing)
LED flashes with a frequency of 0.5 Hz
On time Off time
Display type 2 (double flashing)
LED flashes with a frequency of 0.5 Hz On time 1,2 = 100 ms
Off time 1
Off time 2 = 1700 ms Display type 3 (rapid flashing) LED flashes with a frequency of 2 Hz
On time Off time
Display type 4 (rapid flashing) LED flashes with a frequency of 10 Hz
On time Off time
Display type 5 (on)
The LED is continuously on
Display type 6 (OFF)
In addition, the checkback of faults and of statuses deviating from the standard status is performed with signal 3 at the interior light output. An audible checkback via the alarm horn output also takes place at the alarm center, together with a visual checkback via the outputs for the direction indicator lights. The following signals are defined:
The outputs are triggered once Signal 2
The outputs are triggered twice On time 1,2 = 50 ms
The outputs are triggered once
Assignment of the display type of the alarm Operating conditions readiness light for the
Display type operating state Operating state during inactive period
Self-test ok, central locking system locked and secured, all inputs in normal position,
Self-test ok, central locking system locked, all inputs in normal position, not locked 3 x, subsystems switched off
Not primed central locking system cannot be locked,
Not primed central locking system cannot be locked,
Self-test ok, central locking system locked, ac-
Self-test ok, locking/priming by locking 3 x
Inactive period expired
All inputs inactive, central locking system locked and secured, not locked 3 x, no alarm, subsys-
All inputs inactive, central locking system locked, no alarm, not locked 3 x, subsystems passive
Primed for all non-active inputs
During or after alarm output
Priming/locking command by 3 x rapid
Self-test not in order
If a control command is issued via the remote control, this is confirmed with display type 4 for the duration of the operation. This display has priority. Alarm triggering and alarm output
The alarm functions can be triggered only in the primed state.
A non-blocked alarm input triggers an alarm in the primed state with an active signal. The alarm-triggering input then remains blocked for further alarm triggering until it returns to the inactive state. Then, following expiry of the inactive period of 10 seconds, it is again included in the alarm evaluation, provided that it was inactive for the entire inactive period.
In a priming cycle, the inputs Passenger compartment monitor, External 1 and External 2 trigger a maximum of three alarms.
depending on the country depending on the country asynchronous with the direction indicator lights, depending on the country
The alarm output with all associated actions is interrupted immediately in the event of deactivation,
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