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Anti-theft alarm system trigger, function (MODEL 204.0 with CODE (551) up to Model Year 8) - GF80.50-P-2004CW

MODEL 204.0 with CODE (551) Anti-theft alarm system (ATA [EDW]) up to model year 08/YoM 07 

Function requirements: 

General 

If one of the alarm inputs of the activated ATA exits its non-actuated state, an alarm is triggered.

IMPORTANT Alarm actuation in the event of undervoltage

The operating voltage range of the ATA is defined from U = 8.5 to 15.5 V. If the voltage drops below ≤8.5 V, it is no longer possible to trigger a visual alarm output. Only an acoustic alarm is triggered. The battery voltage is stored in the ATA alarm memory in the rear SAM control unit with fuse and relay module (N10/2).

Function sequence for ATA alarm actuation, general 

The ATA alarm actuation comprises several partial functions. These are:

Function sequence for alarm actuation by opening a door, trunk lid or engine hood 

The rear SAM control unit actuates an alarm as soon as the non-actuated state of one of the following switches is interrupted for t > 0.5 s:

The status of the front door rotary tumbler switch is transmitted by the left front door control unit (N69/1) and right front door control unit (N69/2) to the rear SAM control unit with interior CAN. The remaining switches are read in directly by the rear SAM control unit.

For a new alarm actuation, the corresponding switch must first change to the non-actuated state (debounce time t = 500 ms).

After a non-actuated state of t = 10 s an alarm can be reactuated by the same switch, if an acoustic alarm is not present.

IMPORTANT If a locked vehicle is unlocked with the mechanical key and the door is opened, the ATA triggers an alarm.

Alarm actuation due to change of vehicle inclination 

Additional function requirements 

Function sequence for alarm actuation due to change of vehicle inclination 

If the inclination sensor integrated into the alarm siren recognizes an alarm-relevant inclination, an alarm is output. The corresponding signal is relayed to the rear SAM control unit with the rear SAM-LIN.

Actuation criterion:

Alarm actuation by motion in the interior compartment 

Additional function requirements 

Function sequence for alarm actuation from motion in interior compartment 

The interior protection and tow-away protection control unit (N26/6) is read in by the rear SAM control unit with rear SAM-LIN.

If a movement in the vehicle interior is recognized and considered to be alarm-relevant, an alarm is output.

IMPORTANT During activated rain closing on vehicles with tilting/sliding roof (SR) (with code (414) Power glass tilting/sliding roof) or panoramic roof (with code (413) Panoramic glass roof with top sliding roof), the interior compartment is not monitored. After closing or after expiration of t = 35 s, the interior protection is reactivated.

Function sequence for alarm triggering from communication loss to alarm siren 

The alarm siren is actuated cyclically approx. every t = 700 ms by the rear SAM control unit with rear SAM-LIN. If a reply to this request is not received within t = 1 s by the alarm siren (no communication), the rear SAM control unit and alarm siren trigger an alarm. If the alarm siren detects a loss in the supply voltage, it also outputs an acoustic alarm automatically.

IMPORTANT An alarm is only repeated if a new alarm event is registered after the active acoustic alarm was terminated.

Function sequence for emergency opening 

The trunk lid emergency opening switch (S88/10) ensures that the trunk lid can also be opened from the inside of the trunk lid when the vehicle is locked. The rear SAM control unit reads in and evaluates the trunk lid emergency opening switch. The ATA triggers an alarm when the trunk lid emergency opening switch is actuated.

Function sequence for alarm output 

The following components of the exterior lights are actuated:

The acoustic alarm is output by actuating the alarm siren by the rear SAM control unit with rear SAM-LIN.

The interior lights are switched on by the front SAM control unit.

Function sequence for alarm interruption 

An alarm is interrupted by opening the central locking (CL) of the vehicle with the transmitter key (A8/1) or by switching on circuit 15C (valid transmitter key inserted into electronic ignition switch control unit (N73).

The electronic ignition switch control unit transmits the corresponding signal with interior CAN to the rear control unit, which then terminates the activated alarm.

REFER TO SYSTEM WIRING DIAGRAMS Function schematic for electric anti-theft alarm system, alarm actuation   PE80.50-P-2053-99FAA 
  Door lock, component description A85, A85/1, A85/3 and A85/4 GF80.20-P-4124CW 
  Lamp unit, component description E1, E2 GF82.10-P-2017CW
  Rear lamp unit component description E3, E4 GF82.10-P-2018CW
  Alarm siren, component description H3/1 GF80.50-P-6060CW 
  Trunk lid central locking motor, component description M14/7 GF80.20-P-4123CW 
  Front SAM control unit with fuse and relay module, component description N10/1 GF54.21-P-6070CW
  Rear SAM control unit with fuse and relay module, component description N10/2 GF54.21-P-6030CW
  Interior protection and tow-away protection control unit, component description N26/6
For code (882) Interior monitoring (with ATA [EDW] only)		 GF80.50-P-4130CW 
  Left front door control unit, component description N69/1 GF72.29-P-6001CW
  Right front door control unit, component description N69/2 GF72.29-P-6009CW
  Electronic ignition switch control unit, component description N73 GF80.57-P-6001CW 
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