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GF80.50-P-2004MCU Anti-Theft Alarm System Trigger, Function



GF80.50-P-2004MCU Anti-theft Alarm System Trigger, Function
- with CODE (V01) Anti-theft alarm system (FFO)







1 Doors status
2 Rear-end door status
3 Signal, motions in the interior compartment
4 Communication check
5 Status change for inclination sensor
6 Actuating of alarm siren
7 Actuating turn signal lights
8 Alarm interruption
B32 ATA [EDW] microwave sensor
E1e5 Left turn signal lamp
E2e5 Right turn signal lamp
E3e11 Left brake/turn signal light
E4e11 Right brake/turn signal light
E22/1 Left additional turn signal lamp
E22/2 Right additional turn signal lamp
H3/2 Alarm siren with inclination sensor
L11 Transponder coil
N10/10 SAM control unit
S2/1 Ignition/starter switch
S15 remote trunk opening switch (on model 451.3)
S17/8 Trunk lid rotary tumbler microswitch (on model 451.4)
S87/6 Right door rotary tumbler microswitch
S87/7 Left door rotary tumbler microswitch
A Transmitter key
LIN C Local interconnect network, interior 2 (LIN C)

Function requirements:
^ Anti-theft alarm system (ATA) activated

Function
The ATA evaluates the following alarm inputs:
^ Left rotary tumbler microswitch
^ Right rotary tumbler microswitch
^ Trunk lid rotary tumbler microswitch
^ Remote trunk opening switch
^ Alarm siren with inclination sensor
^ ATA [EDW] microwave sensor

If it detects a change of state in one of the monitored inputs, it triggers a country-specific acoustic and visual alarm.

Alarm actuation via switch
The following components are read in directly by the SAM control unit:
^ Left rotary tumbler microswitch
^ Right rotary tumbler microswitch
^ Trunk lid rotary tumbler microswitch
^ Remote trunk opening switch

If the switch exits its non-actuated state, a visual alarm is triggered by the SAM control unit by actuating the turn signal lights as well as the additional turn signal lamps.
Moreover, the SAM control unit requests an acoustic alarm from the alarm siren via LIN C.
If the rear-end door upper section is opened via the trunk lid remote opening feature, the remote trunk opening switch is deactivated as an alarm input.

If the vehicle is unlocked by mechanically unlocking the driver lock, a visual and acoustic alarm is triggered when the driver door is opened.

Alarm actuation by alarm siren
The alarm siren is actuated cyclically by the SAM control unit. If no answer is received from the alarm siren within approx. 1 s, an alarm is triggered. The alarm is only output visually, as the alarm siren cannot be addressed
If the alarm siren detects loss of the supply power or the communication to the SAM control unit, it outputs an acoustic alarm automatically.

Alarm triggering by tow-away protection
The SAM control unit checks cyclically the input of the inclination sensor integrated into the alarm siren.
If the inclination sensor detects a position change of the vehicle, it relays a signal to the SAM control unit, which requests the acoustic alarm output from the alarm siren via LIN C. Moreover, a visual alarm is output by the SAM control unit by directly actuating the turn signal lights and additional turn signal lamps.

Alarm triggered by interior motion sensor
The alarm decision is accomplished by considering the duration and the speed of the motion in the interior compartment.
If the ATA microwave sensor recognizes forced entry into the vehicle, it relays a signal to the SAM control unit. This outputs a visual alarm via the turn signal lights and additional turn signal lights and requests an acoustic alarm from the alarm siren via LIN C.

If the rear-end door upper section is opened with the trunk lid remote opening function, the interior protection function is deactivated as long as it is open.

Visual alarm
The alarm is output via the SAM control unit, which directly actuates the turn signal lights and additional turn signal lamps. The type of alarm and the alarm duration are stored in the SAM control unit.

Acoustic alarm
The acoustic alarm is output via the alarm siren. The alarm duration is approx. 25 s.
The alarm is requested via the alarm siren in the event of recognized communication loss; otherwise via the SAM control unit.

Alarm interruption
An activated alarm is interrupted by:
^ Circuit 15 On or
^ Actuating lock or unlock button on transmitter key:

Circuit 15 On:
After inserting the transmitter key into the ignition/starter switch, the ID code of the transmitter key is received inductively by the transponder coil when circuit 15 is On.

It discreetly relays the ID code to the SAM control unit for checking. If the ID code is valid, the alarm is deactivated by the SAM control unit.

Actuating lock or unlock button on transmitter key:
The SAM control unit receives the request for alarm interruption by actuating the lock or unlock button on the transmitter key. This checks the validity of the transmitter key. If the transmitter key is valid, the alarm is deactivated by the SAM control unit.

If the alarm is interrupted by actuating the lock button on the transmitter key, the ATA remains activated. The previous status of the tow-away protection and interior protection is maintained.