GF80.50-P-2004GM Anti-Theft Alarm System Trigger, Function
GF80.50-P-2004GM Anti-Theft Alarm System Trigger, Function
- with CODE (551) Anti-theft alarm system (ATA [EDW])
General function requirements
^ Anti-theft 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 U ≤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 (N10/8).
The anti-theft alarm system function alarm actuation comprises the following partial functions:
^ Function sequence for alarm triggering by opening a door, tailgate or engine hood
^ Function sequence for alarm actuation by changing vehicle noninclination (without code (494) USA version, without code (460) Canada version or without code (498) Japan version)
^ Function sequence for alarm triggering by motion in interior compartment (with code (882) Interior monitoring (only with ATA))
^ Function sequence for alarm actuation by communication loss to alarm siren (H3/1) (without code (494) USA version) or alarm horn (H3) (with code (494) USA version)
^ Function sequence for alarm output
^ Function sequence for alarm interruption
Function sequence for alarm triggering by opening a door, tailgate or engine hood
The rear SAM control unit actuates an alarm as soon as the nonactuated state of one of the following switches is interrupted for t > 0.5 s:
- Switch in rear-end door locking unit (A72)
- 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)
- Engine hood ATA switch (S62)
- Spare tire carrier lock switch (S151/1) (on model 164 with code (849) Spare tire carrier/spare wheel)
The 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.
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
^ Tow-away protection not previously deactivated
Function sequence for alarm actuation due to change of vehicle inclination
If the inclination sensor integrated into the rear SAM control unit recognizes an alarm-relevant inclination, an alarm is output. Actuation is accomplished when the vehicle inclination changes by 1° to -1°, ±0.2° (around horizontal axis).
Alarm is triggered before a wheel looses ground contact when lifting the vehicle.
Additional function requirements for alarm triggering by motion in interior compartment
^ Interior protection function not previously deactivated
Function sequence for alarm actuation from motion in interior compartment
The interior protection sensor in the overhead control panel control unit (N70) recognizes motion in the vehicle interior.
If a movement in the vehicle interior is recognized and considered to be alarm-relevant, an alarm is output.
If glass breakage is detected, an additional alarm is triggered. The signals from the left rear glass breakage sensor (B39), right rear glass breakage sensor (B39/1) and rear window glass breakage sensor (B39/4) are read by the overhead control panel control unit.
The overhead control panel control unit transmits the status of the glass breakage sensors via the interior CAN to the rear SAM control unit which starts an acoustic and visual alarm.
The interior compartment is not monitored during convenience closing. The interior protection function is reactivated after completion of the convenience closing operation.
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. The interior protection function is reactivated after closing.
Function sequence for alarm actuation by communication loss to alarm siren or alarm horn
The alarm siren or alarm horn are actuated cyclically approx. every t = 700 ms by the rear SAM control unit. If the alarm siren or alarm horn does not respond within t = 1 s (no communication), the rear SAM control unit actuates an alarm. In this case the alarm is output only visually.
Function sequence for alarm output On vehicles without code (494) USA version
On vehicles without code (494) USA version the following exterior light components are actuated.
- by the front SAM control unit (N10):
- Left turn signal lamp (E1e5)
- Right turn signal lamp (E2e5)
- By the rear SAM control unit:
- Left turn signal lamp (E3e1) (on model 251, model 164 without code (849) Spare tire carrier/spare wheel)
- Right turn signal lamp (E4e1) (on model 251, model 164 without code (849) Spare tire carrier/spare wheel)
- Left turn signal lamp (E3/5e1) (on model 164 with code (849) Spare tire carrier/spare wheel)
- Right turn signal lamp (E4/5e1) (on model 164 with code (849) Spare tire carrier/spare wheel)
- by the left front door control unit (N69/1):
- Left outside mirror turn signal lamp (E6/5)
- by the right front door control unit (N69/2):
- Right outside mirror turn signal lamp (E6/6)
The acoustic alarm is output by the alarm siren, which is actuated directly by the rear SAM control unit.
The interior illumination is switched on by the overhead control panel control unit after request by the rear SAM control unit via interior CAN.
The following components of the exterior lights are actuated on vehicles without code (494) USA version:
- by the front SAM control unit:
- Left front fog lamp (E5/1)
- Right front fog lamp (E5/2)
- by the rear SAM control unit:
- Left brake light, taillamp, parking light and left side marker lamp (E3e9)
- Right brake light, taillamp, parking light and left side marker lamp (E4e9)
The acoustic alarm is output by the alarm siren, which is actuated directly by the rear SAM control unit.
The interior illumination is switched on by the overhead control panel control unit after request by the rear SAM control unit via interior CAN.
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.
