GF80.50-P-2004RC Antitheft Alarm System Trigger, Function
GF80.50-P-2004RC Antitheft Alarm System Trigger, Function
- with CODE (551) Anti-theft alarm system (ATA [EDW])
General function requirements
^ Antitheft alarm system (ATA) activated
ATA alarm triggering, general
If one of the alarm inputs of the activated ATA exits its non actuated state, an alarm is triggered.
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 central grate control unit (N93).
The ATA alarm triggering comprises the following subfunctions:
^ Function sequence for alarm actuation by contact switch
^ Function sequence for alarm actuation due to change of vehicle inclination
^ Function sequence for alarm triggering by motion in interior compartment (with code (882) Interior monitoring (only with ATA))
^ Function sequence for alarm actuation from communication loss to alarm siren (H3/1)
^ Function sequence for alarm output
^ Function sequence for alarm interruption
Function sequence for alarm actuation by contact switch
The rear SAM control unit with fuse and relay module (N10/2) triggers an alarm as soon as one of the following switches is set to the non-actuated state for t > 0.5 s:
- Left door contact switch (S17/3)
- Right door contact switch (S17/4)
- Engine hood ATA switch (S62)
- Glove box switch, ATA (S62/7)
- ATA [EDW] center console compartment switch (S62/8)
- Trunk lid rotary tumbler microswitch (S88/1)
The status of the switch is 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.
Additional function requirements for alarm triggering by changing vehicle inclination
^ Tow-away protection not deactivated
Function sequence for alarm actuation due to change of vehicle inclination
The rear SAM control unit checks the input of the ATA inclination sensor (B33) several times per second. If the ATA inclination sensor recognizes a position change of the vehicle, an acoustic and optical alarm is triggered by the rear SAM control unit.
Actuation criterion:
- Alarm recognition when vehicle inclination is changed 3° - 3.5° in relation to horizontal axis) or in the event of a speed change of 1° ± 0.5° per minute
- Vehicle inclinations below 0.5° do not trigger an alarm
- Towing sensor alarm occurs before a wheel loses ground contact when lifting the vehicle
Additional function requirements for alarm triggerings by motion in interior compartment
^ Interior protection not deactivated
Function sequence for alarm actuation from motion in interior compartment
The alarm decision is made with regard to duration and speed of the motion in the passenger compartment by the interior protection transmitter and receiver (A26/14).
The interior protection transmitter and receiver unit transmits the corresponding signal to the overhead control panel control unit (N70) via a serial interface. The overhead control panel control unit transmits via the interior CAN to the rear SAM control unit, which triggers an acoustic and visual alarm.
Function sequence for alarm triggering from communication loss to alarm siren
If the bi-directional communication between the alarm siren and the rear SAM control unit is interrupted (cycle time with three repetitions is between t = 350 ms and 450 ms), an alarm is output for the specific country.
If the alarm siren detects a loss of the supply power or communication, it outputs an acoustic alarm automatically (except on vehicles with code (494) USA version, with code (460) Canada version or with code (498) Japan version) because an alarm siren with additional battery is installed here).
An alarm is only repeated if a new alarm event is registered after the active acoustic alarm was terminated.
Function sequence for alarm output
The following components of the exterior lights are actuated:
On vehicles with code (494) USA version:
- by the driver-side SAM control unit with fuse and relay module (N10/1):
- Left front fog lamp (E5/1)
- Right front fog lamp (E5/2)
- by the rear SAM control unit:
- Left brake light, taillight and parking lights (E3e9)
- Right brake light, taillight and parking lights (E4e9)
On vehicles without code (494) USA version:
- by the driver-side SAM control unit with fuse and relay module:
- Left turn signal light (E1e5)
- Right turn signal light (E2e5)
- by the rear SAM control unit:
- Left turn signal light (E3e1)
- Right turn signal light (E4e1)
- by the left door control unit (N69/1):
- Left outside mirror turn signal lamp (E6/5)
- by the right door control unit (N69/2):
- Right outside mirror turn signal lamp (E6/6)
The acoustic alarm is output by actuating the alarm siren in the rear SAM control unit.
The overhead control panel control unit switches on the interior illumination. The instrument cluster (A1) activates the left turn signal indicator lamp (A1e1) and right turn signal lamp indicator lamp (A1e2).
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 interior CAN to the rear SAM control unit, which then terminates the activated alarm.
