The antitheft alarm system (DWA) is controlled by the general module of the central body electronics (ZKE).
The following inputs are monitored:
An acoustic and visual alarm (country-specific coding) is triggered.
The antitheft alarm system is activated automatically together with locking/arming of the central locking system (arming = ignition OFF, open and close driver's or front passenger's door, lock vehicle via lock cylinder or radio remote control).
The inputs are monitored after arming and a waiting time of 3 seconds. This waiting time makes it possible to close the door for instance shortly after arming the antitheft alarm system. If, after arming, one or several input signals are not in rest position (e.g. door open) the status LED will flash for 10 seconds. A switch which is not in rest position is not included in the monitoring function.
The tilt alarm sensor and the interior protection are switched off if the antitheft alarm system is armed within 10 seconds after arming it for the first time (key turned once again in door lock or corresponding button on remote control pressed). In this way, the risk of a false alarm is avoided under certain conditions (e.g. car trains or ship transport).
LED indicator
A light emitting diode (LED) which signals the DWA status serves as visual feedback. This LED is located on the rear-view mirror.
DWA LED |
DWA status |
OFF |
Disarmed |
Permanent rapid flashing |
Armed |
Flashes for 10 seconds followed by permanent rapid flashing |
Input not in rest status |
Lights for 1 second followed by permanent rapid flashing |
Re-arming (tilt alarm sensor and interior protection are blanked out) |
Flashes for 5 minutes followed by permanent rapid flashing |
Alarm triggering |
Flashes for 10 seconds then goes out |
Disarming after alarm |
The DWA LED flashes at a rate of once every 2 seconds. It blinks at a rate of twice per second.
The status of the input signals can be red out via diagnosis. This enables rapid troubleshooting in the event of an LED flashing after arming.
Additional feedback concerning arming and disarming (country-specific) can be set by way of coding.
DWA status |
Visual acknowledgment |
Acoustic acknowledgment |
Arming |
1x warning flash |
1 short tone signal |
Disarming |
2x warning flash |
2 short tone signals |
The alarm is triggered by the general module. A siren serves as the acoustic signal generator.
The siren is activated for 30 seconds in the case of alarm. The alarm is interrupted immediately when the antitheft alarm system (DWA) is disarmed. The siren can be coded to permanent tone or intermittent tone (country-specific).
A visual alarm is triggered for approx. 5 minutes together with the acoustic alarm. The light switch centre switches on the lights via the K-bus. The lights (only hazard warning or additionally low beam or high beam) to be activated as the visual alarm are coded country-specific in the general module.
The input responsible for alarm triggering is stored in the alarm memory in the general module. The alarm memory can be read out in the diagnostic program and deleted with "delete fault code memory".
The electronic control and the battery are integrated in the siren. This ensures it can be activated independent of the vehicle electrical system.
The siren is primed and deactivated via a line STDWA (the same line also activates and deactivates the tilt sensor and interior protection facility). The siren is informed of the alarm triggering status by the general module via the SIREN line. When the siren is armed, an alarm may still be triggered if the siren is disconnected from the vehicle electrical system or the vehicle battery is disconnected.
If the alarm is triggered by tampering with the emergency current siren, the alarm is not stored in the alarm memory as the general module cannot register the alarm.
If the upper tailgate is opened via the remote control with the antitheft system armed, the tailgate contact, interior protection system and the tilt sensor for triggering the alarm are deactivated.
It may be possible that the antitheft alarm system (DWA) can no longer be disarmed in the event of the remote control or central locking systems failing. In this case, the emergency disarming procedure must be implemented to disarm the antitheft alarm system (DWA), however, an alarm will now be triggered.
Procedure:
The emergency disarming procedure is terminated if a door is opened or the setting of the ignition lock is changed during this waiting period.
Repeated emergency disarming can only be restarted after the alarm period has elapsed (5 minutes).
A vehicle alarm can be triggered via the remote control by pressing the "boot lid/panic" button on the remote control key for longer than 1 second.
This panic mode triggers an acoustic and visual alarm irrespective of the current DWA status. Panic mode is terminated by disarming or arming the antitheft alarm system (DWA) as well as by unlocking the doors with the key.