System description
The anti-theft alarm is automatically enabled if the key is left in the driver-side door lock for more than 1.5 seconds in the locked position, or the vehicle is locked using the remote control. If a door is still open, the ATA is not enabled when the vehicle is locked.
The turn signal lamps come on briefly when the ATA is activated. As a function check, the monitoring lamps in the panic switch flash when the ATA is enabled.
If the vehicle is centrally unlocked from the outside at the driver-side door or using the remote radio control (FFB), the ATA is disabled.
If the vehicle is unlocked at the passenger-side door or the loading area door, an alarm is triggered.
Whilst the ATA is active, an alarm sounds if:
a door is opened,
a door is unlocked from the inside,
the hood is opened,
a trailer connector is uncoupled (vehicles with trailer couplings and trailers connected before enabling the ATA),
the central locking is unlocked using the key at any place other than the driver-side door.
Acoustic alarm: Auxiliary horn sounds at about 30 second intervals.
Optical alarm: The turn signal lamps flash for about 5 minutes. The alarm is immediately disabled if the vehicle is centrally unlocked at the driver-side door or using the remote radio control (FFB).
Panic switch
Operating the panic switch immediately activates an acoustic and optical alarm. If all doors are closed, the vehicle is completely locked. The monitoring lamps in the switch flashes at the same frequency as the turn lamps. The alarm is disabled when the switch is reset and the vehicle is unlocked again.
Trailer monitor
If a trailer coupling is being used, disconnection is detected via the trailer turn signal lamps and an alarm is triggered. A trailer that is connected after activation has taken place is not monitored.
Note
The last 5 alarm causes are stored in the control module EEPROM and can be read out via the diagnosis interface.