GF80.50-P-2002RC Activate Antitheft Alarm System, Function
GF80.50-P-2002RC Activate Antitheft Alarm System, Function
- with CODE (551) Anti-theft alarm system (ATA [EDW])
General function requirements
^ C.15C OFF
Activate antitheft alarm system (ATA), general
The ATA is activated automatically when the vehicle is locked with the central locking (CL). Then the individual alarm inputs are monitored. The activated ATA is indicated by an LED flashing permanently in the interior CL close switch and ATA function display (N72/1s17).
On vehicles for Belgium, the ATA arms automatically without locking the vehicle with the CL.
It is possible to switch off the tow-away protection or on vehicles with code (882) Interior monitoring (only with ATA) the interior protection feature before locking with the CL.
Activation of the ATA comprises several subfunctions:
^ Function sequence for activating ATA
^ Function sequence for switching off tow-away protection of ATA
^ Function sequence for switching off interior protection of ATA (with code (882) Interior monitoring (only with ATA))
^ Function sequence for activating alarm inputs
^ Function sequence for convenience feature
Function sequence for activating ATA
Activation of the ATA comprises several subfunctions:
^ Function sequence for locking with transmitter key (A8/1)
^ Function sequence for locking CL with automatic relocking feature
^ Function sequence for self-activation (Belgium only)
Special case: Driver door
If the driver door is still open when the CL is locked, it is not locked. When the driver door is closed, the door status is indicated to the rear SAM control unit with fuse and relay module (N10/2) and the alarm input is included in the checking cycle. This leads to actuation of an alarm when opening the driver door without previous deactivation of the ATA.
Function sequence for locking CL with transmitter key
When the "lock" button on the transmitter key is actuated, it transmits a radio signal to the rear SAM control unit via the left antenna amplifier module (A2/64). This relays the signal to the EIS control unit (N73) via the interior CAN..
Parallel to the radio signal, an infrared signal is transmitted to the left IR receiver unit (A26/1) (with code (880) Closing system with infrared remote control) or right IR receiver unit (A26/2) (with code (880) Closing system with infrared remote control ) (precise aiming required).
The corresponding signal is read in by the left door control unit (N69/1) or right door control unit (N69/2) and transmitted to the EIS control unit via interior CAN.
In both cases, the EIS control unit checks the access authorization of the transmitter key.
If the access authorization is valid, the vehicle is locked with the CL. Then the rear SAM control unit activates the ATA.
Function sequence for locking CL with automatic relocking feature
The automatic relocking function is actuated by the EIS control unit. If the vehicle is unlocked and neither a door nor the trunk lid is opened within 40 s, the vehicle relocks automatically. The EIS control unit transmits via interior CAN the message "Relocking" to the rear SAM control unit, which then activates the ATA.
Function sequence for self-activation
When the transmitter key is removed from the EIS control unit, the driver door or the trunk is opened and closed again, the ATA is activated automatically 2 s after the last door or the trunk lid is closed, regardless of the status of the vehicle central locking. The interior protection and the tow-away protection are set to the same state as before the last unlocking procedure.
Additional function requirements for switching off tow-away protection of ATA
^ ATA not activated
Function sequence for switching off tow-away protection of ATA
Actuation of the TS [AS] OFF switch (S84s3) is read in by the upper control panel control unit (N72/1). The request is transmitted to the rear SAM control unit via the interior CAN. It deactivates the tow-away protection for the following activation of the ATA. Deselection of the tow-away protection is confirmed by the function indicator flashing in the TS [AS] OFF switch for approx. t = 2 s after releasing the TS [AS] OFF switch.
Additional function requirements for switching off interior protection of ATA
^ ATA not yet activated
Function sequence for switching off interior protection of ATA
Actuation of the IMS [IRS] OFF switch (S84s2) is read in by the upper control panel control unit.
The request is transmitted to the rear SAM control unit via the interior CAN. It deactivates the interior protection for the following activation of the ATA. Deselection of the interior protection is confirmed by the function indicator flashing for approx. t = 2 s in the IMS [IRS] OFF switch at f = 6,25 Hz (t = 80 ms ON, t = 80 ms OFF).
Additional function requirements for activating alarm inputs
Activating alarm inputs comprises the following partial functions:
^ Function sequence for monitoring switch
^ Function sequence for activating tow-away protection
^ Function sequence for activating interior protection (with code (882) Interior monitoring (only with ATA))
^ Function sequence for activating alarm siren (H3/1)
Function sequence for monitoring switch
The status of the following switches is checked cyclically every t = 0.5 s. If the polls indicate that an input is at rest within t = 10 s, the corresponding input is then armed.
Alarm inputs set later to the non-actuated state, e.g. if the trunk lid is closed only after the vehicle has been locked, are also armed t = 10 s after closing.
Monitored switches:
- 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)
- Rotary tumbler/trunk lid microswitch (S88/1)
Function sequence for activating tow-away protection
The tow-away protection is activated (if not previously deselected for the next locking operation) t = 10 s after the locking command from the EIS control unit and after closing the last door and trunk lid.
The ATA inclination sensor (B33) determines a reference position with which the relative vehicle inclination is compared during the activation time. Determination of the reference position takes approx.
t = 10 s. For this purpose an alarm can be actuated approx.
t = 30 s after arming at the earliest.
The ATA inclination sensor communicates directly with the rear SAM control unit. When the maximum vehicle inclination is exceeded with regard to the reference position, an alarm is triggered.
If the vehicle inclination changes very slowly (e.g. leaky tire), the reference position adapts to the current vehicle position to prevent inadvertent activation of the ATA inclination sensor.
If the ATA inclination sensor is faulty, all other components of the ATA continue to function properly and the corresponding fault codes are entered in the fault memory in the rear SAM control unit.
Function sequence for activating interior protection
The interior protection is activated (if not previously deselected for the next closing) t = 30 s after the last door or the trunk is closed. The interior protection transmitter and receiver unit (A26/14) is installed in the overhead control panel control unit (N70). The interior protection transmitter and receiver unit operates as a reflection sensor/heat detector. During operation, it checks changes in the IR light reflected from the interior. This is amplified and then evaluated. During an alarm actuation, the overhead control panel control unit relays the signal to the rear SAM control unit via the interior CAN.
The status of the interior protection transmitter and receiver unit is also monitored by the rear SAM control unit. If a defect is detected, the remaining ATA functions are still ensured regardless of this error. The corresponding fault codes are stored in the fault memory in the rear SAM control unit.
Special case Vario roof open:
In general the interior protection is not switched on when the Vario roof is opened.
Except vehicles for the Netherlands: The interior protection is also activated when the Vario roof is open.
Function sequence for activating alarm siren
The alarm siren is armed together with the ATA and check cyclically approx. every t = 700 ms by the rear SAM control unit
Visual feedback:
The function indicator in the in the lock CL [ZV] interior switch and ATA [EDW] function indicator comes on momentarily once each second.
Acoustic feedback:
On vehicles for the Netherlands with code (494) USA version and with code (460) Canada version, a buzzer signal is generate (triple beep). The buzzer signals have different sounds. If one door is not properly closed during ATA [EDW] activation, no feedback will be given.
Deactivating ATA:
The ATA is deactivated completely by opening the CL with transmitter key with infrared or radio or by switching on circuit 15C (valid transmitter key in EIS control unit). The EIS control unit transmits the corresponding signal via interior CAN to the rear SAM control unit, which then activates the ATA.
On vehicles with code (494) USA version or with code (460) Canada version, an alarm siren without additional battery is installed.
Function sequence for convenience feature
The remote trunk release function is a convenience function allowing the driver to open the trunk lid with the transmitter key. The trunk lid is also an alarm input and this function must also be available when the vehicle is locked (ATA armed).
This makes it necessary for the ATA to support the trunk lid function in a manner that resets the ATA to its original status after completing the remote trunk lid opening function and does not generate an alarm.
With the remote trunk lid opening function only the alarm inputs for the trunk lid contact, interior protection and tow-away protection are disarmed. All other ATA alarm inputs remain armed, i.e. in status ready for alarm.
The interior protection and tow-away protection are disarmed following the remote trunk lid opening function.
The trunk lid contact is accepted as an alarm input depending on the signal "Trunk lid lock locked".
The central locking is a convenience function allowing the driver to close the windows and the Vario roof with the transmitter key (infrared). With this convenience function the ATA can be in the arming phase or is already in the armed state. It is necessary to deactivate the interior protection for the duration of the convenience function so that the movements of the windows and the Vario roof do not cause erroneous interior protection alarms. Following convenience closing, the interior protection is always rearmed unless it has been deselected with the IMS [IRS] OFF.
The convenience function can be activated via the air recirculation buttons on the:
- HEAT control and operating unit (N18) (without code (580) Automatic air conditioning and without code (581) Comfort automatic air conditioning)
- AAC [KLA] control and operating unit (N22) (with code (580) Automatic air conditioning)
- Comfort AAC control and operating unit (N22/7) (with code (581) Comfort automatic air conditioning)
or by the infrared command via the left door control unit and right door control unit.
As soon as the rear SAM control unit (only with armed ATA) receives a convenience message from one of these control units, the rear SAM control unit transmits the corresponding message for deactivating the interior protection to the overhead control panel control unit, which deactivates the interior protection. The remaining ATA components remain armed and ready for alarm.
