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Anti-theft alarm system trigger, function - GF80.50-P-2004LE

MODEL 221.0 /1, 216.3 as of model year 09 /YoM 08 with CODE (551) Anti-theft alarm system (ATA [EDW]) 

General function requirements 

Anti-theft alarm system alarm triggering, 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 to 16 V. If the voltage drops below U ≤8 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).

The ATA alarm triggering comprises the following partial functions:

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 rotary tumbler is read in by the

and transmitted to the rear SAM control unit via the interior CAN.

The ATA engine hood switch and the trunk lid rotary tumbler microswitch are read in directly by the rear SAM control unit. To trigger a new alarm, the corresponding switch must first change to the non-actuated state.

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.

Additional function requirements for alarm triggering by changing vehicle inclination 

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:

IMPORTANT Alarm is recognized before a wheel looses ground contact when lifting the vehicle.

Additional function requirements for alarm triggering by motion in interior compartment 

Function sequence for alarm actuation from motion in interior compartment 

The signals from the ultrasonic echo sounder sensor (A26/13) (with code (882) Interior monitoring (only with ATA)) are read in by the rear SAM control unit.

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

IMPORTANT On vehicles with tilting/sliding roof (SHD) (with code (414) Electric glass tilting/sliding roof) or panoramic sliding roof (with code (413) Panoramic glass sunroof with top sliding sunroof) the interior compartment is not monitored during activated rain closing.

Function sequence for alarm triggering from communication loss to alarm siren 

The alarm siren is actuated cyclically by the rear SAM control unit via the 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 release switch is actuated.

Function sequence for alarm output 

The following components for the exterior lights are actuated to output a visual alarm:

The acoustic alarm is output by the rear SAM control unit actuating the alarm siren via the rear SAM-LIN. The interior illumination is switched on by the overhead control panel control unit (N70).

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 EIS control unit (N73)).

The EIS control unit transmits the corresponding signal via the interior CAN to the rear SAM control unit, which then terminates the activated alarm.

REFER TO SYSTEM WIRING DIAGRAMS Function schematic for electric anti-theft alarm system, alarm actuation Model 216 PE80.50-P-2053-97CAA
Model 221 PE80.50-P-2053-97SAA
  Front SAM control unit with fuse and relay module, component description N10/1 GF54.21-P-6070LE
  Rear SAM control unit with fuse and relay module, component description N10/2 GF54.21-P-6030LE
  Left door control unit, component description N69/1
Model 216		 GF72.29-P-4124LA
  Left front door control unit, component description N69/1
Model 221		 GF72.29-P-4141LE
  Right door control unit, component description N69/2
Model 216		 GF72.29-P-4128LA
  Right front door control unit, component description N69/2
Model 221		 GF72.29-P-4142LE
  Rear door control unit, component description N69/3, N69/4
Model 221		 GF72.29-P-6020LE
  Overhead control panel control unit, component description N70 GF82.20-P-5216LE
  Component description for the EZS control unit N73 GF80.57-P-6003LE 
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