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GF80.50-P-2002RTU Activate Anti-Theft Alarm System, Function



GF80.50-P-2002RTU Activate Anti-Theft Alarm System, Function


Component Identification:






Activate anti-theft alarm system (ATA), code 551
^ Lock central locking (CL) with transmitter key
^ Lock CL with relocking function
^ Lock vehicle with keyless go (KG) (with keyless go, code 889)

Partial activation of ATA
The towing sensor function can be switched off for the next activation of the ATA.

Switch off towing sensor function
The towing sensor can be deactivated for the next arming cycle via the menu in the instrument cluster.

The rear SAM control unit ensures that deactivation commands are no longer processed after the command "ATA active" is set. The instrument cluster outputs a feedback signal indicating the current status of the deactivated towing sensor. The deactivation is possible as long as the vehicle is not locked.

Alarm inputs
The ATA evaluates the following alarm inputs:
^ Rear door locking unit
^ Alarm signal horn (H3)
^ Right front door rotary tumbler microswitch (M14/5s1)
^ Left front door rotary tumbler microswitch (M14/6s1)
^ Left rear door rotary tumbler microswitch (M14/8s1)
^ Right rear door rotary tumbler microswitch (M14/9s1)
^ ATA [EDW] hood switch

The state of the alarm inputs is checked cyclically If all checks within 10 s indicate the non-actuated state, the corresponding input is armed. Alarm inputs switched to non-actuated state later, are also armed after 10 s.

Towing sensor
The towing sensor is activated 10 s after the locking command from the EIS control and after closing the last door or the rear-end door, assuming it was not deselected for the next closing cycle on the instrument cluster. A defect in the inclination sensor has no effect on the function of the remaining ATA. The reference position is determined in approx. 10 s; for this reason, a towing alarm can be accepted only after this time, at the earliest.When the towing function is activated, the inclination sensor determines the current reference position so that it can compare the relative vehicle inclination during this activated time period.When the maximum vehicle inclination is exceeded in terms of the reference position, a towing sensor alarm is triggered.

The inclination sensor is integrated in the rear SAM control unit.

Alarm signal horn
The alarm signal horn is a passive component and is actuated by the rear SAM control unit. There is no communication between the rear SAM control unit and the alarm signal horn.

Special case: Driver door
When the anti-theft alarm system (ATA), code 551, is activated and the driver door is still open, the left front door CL motor is not actuated and the door remains unlocked. This has the effect that the vehicle key cannot be locked in the vehicle.When the driver door is closed, the door status is indicated to the rear SAM control unit and the alarm input is included in the checking cycle; a plausible ATA alarm can occur.If the driver door is opened without previously activating the ATA, an alarm is actuated.

Special case: Convenience open/close function
The windows and the tilting/sliding roof can be opened or closed with the transmitter key via the convenience opening/closing function (with electric glass tilting/sliding roof, code 414).On this convenience function, the ATA can be in the activation phase or is already in the armed state The alarm is deactivated for the duration of the convenience function so that the motions of the windows and tilting/sliding roof do not trigger an alarm. After the convenience opening/closing function the ATA is reset to the same status as before the function

Feedback after successful activation
Visual
Activation of the ATA is indicated by an LED in the ATA function display (N72/1e2) in the upper control panel control unit.

Implausible opening/closing commands
Repetitive or continuous presence of lock/unlock commands has no effect on the function of the ATA.When unlocking or locking commands are transmitted at random, the signal received last always determines the current function status.

Automatic relocking
The automatic relocking function is actuated by the EIS control unit, if the vehicle is unlocked and none of the doors or trunk lid are opened within 40 s. In this case, the vehicle relocks automatically. Relocking is confirmed by feedback. The towing sensor is set to the same state as before the last unlocking procedure. The ATA is armed when relocking

Automatic rear-end door remote release
The rear-end door remote release is a convenience function allowing the driver to open the rear-end door with the transmitter key.Since the rear-end door is also an alarm input and this function should also be available when the vehicle is locked, it is necessary that the ATA supports the rear-end door function so that no alarm is generated and after completion of the rear- end door function, the ATA is reset to its original state

Disarm automatic rear-end door remote release
During the rear-end door remote release function, only the rear end door and towing sensor alarms are disarmed. All other ATA alarm inputs remain armed, i.e. in state ready for alarm.

Rearm after automatic rear-end door remote release
When the rear-end door is closed again after rear-end door remote release, the rear-end door and towing sensor alarm inputs are rearmed.