Activate anti-theft alarm system, function - GF80.50-P-2002FL

MODEL 212 with CODE 551 (Anti-theft alarm system) 

Function requirements, general 

• Circuit 15C OFF
• Central locking operating properly

Activate antitheft alarm system (ATA [EDW]), general 

The ATA is automatically activated with the central locking (CL) when the vehicle is locked. Then the individual alarm inputs are monitored. The activated ATA is indicated by a permanently flashing anti-theft alarm system indicator lamp (S6/1e2) in the instrument panel switch group (S6/1) (up to 28.3.13) or anti-theft alarm system indicator lamp (N72/1e2) the upper control panel control unit (N72/1).

It is possible to switch off the tow-away protection or interior protection (with code (882) Interior monitoring (only with ATA [EDW]) the interior protection feature before locking with the CL.

Activation of the ATA function comprises the following partial functions:

• Function sequence for switching off tow-away protection of ATA [EDW] (with code (882) Interior monitoring (only with ATA [EDW])) 
• Function sequence for switching off interior protection of ATA [EDW] (with code (882) Interior monitoring (only with ATA [EDW])) 
• Function sequence for activating ATA [EDW] 
• Function sequence for activating alarm inputs 

Additional function requirements for tow-away protection of ATA (with code (882) Interior monitoring (only with ATA)) 

• ATA [EDW] not yet activated

Function sequence for switching off tow-away protection of ATA [EDW] (with code (882) Interior monitoring (only with ATA [EDW])) 

The interior protection and tow-away protection control unit (N26/6) directly reads in the status of the tow-way protection button (N70s9) (with code (414) Electric tilting/sliding glass sunroof) or tow-way protection button (N70/3s9) (without code (414) Electric tilting/sliding glass sunroof) and transmits the status via the rear SAM-LIN (LIN B4) to the rear SAM control unit with fuse and relay module (N10/2). Then the rear SAM control unit deactivates the tow-away protection for the following activation of the ATA.

Function feedback:

Deselection of the tow-away protection button is confirmed by an LED in the tow-away protection for approx. t = 2 s after releasing the tow-away protection button. The rear SAM control unit transmits the request for this via the rear SAM-LIN to the interior protection and tow-away protection control unit, which correspondingly actuates the LED in the tow-away protection button.

Additional function requirements for switching off interior monitoring of ATA [EDW] (with code (882) Interior monitoring (only with ATA [EDW])) 

• ATA [EDW] not yet activated

Function sequence for switching off interior protection of ATA [EDW] (with code (882) Interior monitoring (only with ATA [EDW])) 

The interior protection control unit and tow-away protection directly reads in the status of the interior protection button (N70s8) (with code (414) Electric tilting/sliding glass sunroof) or interior protection button (N70/3s8) (without code (414) Electric tilting/sliding glass sunroof) and transmits the status to the rear SAM control unit via the rear SAM-LIN. Then the rear SAM control unit deactivates the interior protection for the following activation of the ATA. On model 212.2 monitoring is additionally deactivated on left rear glass breakage sensor (B39), right rear glass breakage sensor (B39/1) and rear window glass breakage sensor (B39/4).

Function feedback:

Deselection of the interior protection is confirmed by an LED in the interior protection button for approx. t = 2 s after releasing the interior protection button. The rear SAM control unit transmits the request for this via the rear SAM-LIN to the interior protection and tow-away protection control unit, which correspondingly actuates the LED in the interior protection button.

Function sequence for activating ATA [EDW] 

Activation of the ATA [EDW] comprises the following subfunctions:

• Function sequence for locking CL with transmitter key (A8/1) 
• Function sequence for locking CL with automatic relocking feature 
• Function sequence for locking CL with KEYLESS-GO (with code (889) KEYLESS-GO) 

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 and the alarm input is included in the checking cycle.

Function sequence for locking CL with transmitter key 

Vehicles without code (889) KEYLESS-GO:

When the lock button the transmitter key is actuated, it transmits a radio signal (access authorization) via the rear window antenna (A2/32), FM 1, AM, ZV and KEYLESS-GO antenna amplifier (A2/18), rear SAM control unit and interior CAN (CAN B) to the electronic ignition lock control unit (N73).

Vehicles with code (889) KEYLESS-GO:

When the lock button the transmitter key is actuated, it transmits a radio signal (access authorization) to the KEYLESS-GO control unit via rear window antenna, FM 1, AM, ZV and KEYLESS-GO antenna amplifier (N69/5). The KEYLESS-GO control unit sends the access authorization to the electronic ignition lock control unit via the interior CAN.

Parallel to the radio signal (access authorization), the transmitter key transmits an infrared signals via the driver door infrared remote control receiver (A26/1) (precise aiming required) and a direct line to the left front door control unit (N69/1). The left front door control unit transmits this to the electronic ignition lock control unit via the interior CAN.

The electronic ignition switch control unit checks the transmitter key for access authorization. If the access authorization is valid, the electronic ignition switch control unit transmits the request "Unlock" to the corresponding control units via the interior CAN. Then the rear SAM control unit activates the ATA [EDW].

Function sequence for locking CL with automatic relocking feature 

The automatic relocking function is actuated by the electronic ignition lock control unit. If the vehicle is unlocked and neither a door nor the liftgate is opened within 40 s, the vehicle relocks automatically. The electronic ignition switch control unit transmits with interior CAN the message "Vehicle locked" to the rear SAM control unit, which then activates the ATA [EDW].

Function sequence for locking CL with KEYLESS-GO (with code (889) KEYLESS-GO) 

Detailed information on the function sequence locking/unlocking the CL is given in the separate function description "KEYLESS-GO".

Additional function requirements for activating alarm inputs 

• ATA [EDW] activated

Function sequence for activating alarm inputs 

Activating alarm input function comprises the following subfunctions:

• Function sequence for monitoring switch 
• Function sequence for activating tow-way protection (with code (882) Interior monitoring (only with ATA [EDW])) 
• Function sequence for activating interior protection (with code (882) Interior monitoring (only with ATA [EDW])) 
• Function sequence for activating alarm siren (H3/1) (up to 31.5.10, as of 1.6.10 without code (494) USA version) 

Function sequence for monitoring switch 

The following listed switches are interrogated in cycles for their condition every t = 200 ms. 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 (model 212.0/1) or liftgate (model 212.2)) is closed only after the vehicle has been locked, are also armed t = 10 s after closing.

Monitored switches:

• Engine hood switch pedestrian protection + ATA Hall sensor (A38/1) (with code (U60) Pedestrian protection)
• Left front door rotary tumbler switch (A85s1) in left front door lock (A85)
• Right front door rotary tumbler switch (A85/1s1) in right front door lock (A85/1)
• Left rear door rotary tumbler switch (A85/3s1) in left rear door lock (A85/3)
• Right rear door rotary tumbler switch (A85/4s1) in right rear door lock (A85/4)
• Trunk lid rotary tumbler switch (M14/7s1) (model 212.0/1) or liftgate rotary tumbler switch (M14/7s1) (model 212.2)
• Left engine hood contact switch (S62/43) (without code (U60) Pedestrian protection)

The left front door control unit directly reads in the status of the left front door rotary tumbler switch and transmits it to the rear SAM control unit via the interior CAN.

The right front door control unit (N69/2) directly reads in the status of the right front door rotary tumbler switch and transmits it to the rear SAM control unit via the interior CAN (CAN B).

The rear SAM control unit directly reads in the status of the rear door rotary tumbler switch, the trunk lid rotary tumbler switch or liftgate rotary tumbler switch and the status of the pedestrian protection Hall sensor + ATA [EDW] engine hood switch (with code (U60) pedestrian protection) or left engine hood contact switch (without code (U60) Pedestrian protection).

The rear SAM control unit evaluates all relevant information accordingly.

Function sequence for activating tow-way protection (with code (882) Interior monitoring (only with ATA [EDW])) 

The tow-away protection is activated (if not previously deselected for the next locking operation) t = 10 s after the locking command from the electronic ignition switch control unit and after closing the last door and trunk lid or liftgate. The inclination sensor in the interior protection and tow-away protection control unit determines a reference position, with which the relative vehicle inclination is compared during the activation. Determination of the reference position requires approx. t = 10 to 15 s, for this reason an alarm can only be triggered t = 30 s at the earliest after arming. The inclination sensor communicates with the rear SAM control unit with rear SAM-LIN. When the maximum vehicle inclination is exceeded with regard to the reference position, an alarm is triggered.

Function sequence for activating interior protection (with code (882) Interior monitoring (only with ATA [EDW])) 

The interior protection is activated (if not previously deselected for the next closing) t = 10 s after the last door and the trunk lid or the liftgate is closed. The interior protection is ready for an alarm only after another t = 20 s, because it is first necessary to calibrate the interior protection and tow-away protection control unit to match the vehicle interior. On model 212.2 the glass breakage sensors are monitored additionally.

The status of the interior protection control unit and the tow-away protection is 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.

Function sequence for activate alarm siren (up to 31.5.10, as of 1.6.10 without code (494) USA version) 

The alarm siren is armed together with the ATA [EDW] and checked cyclically approx. every t = 700 ms by the rear SAM control unit with rear SAM-LIN.

Deactivating ATA: The ATA is completely deactivated when the CL is unlocked by the infrared or RF signal from the remote control key, or by switching on circuit 15C. The electronic ignition switch control unit transmits the corresponding signal with interior CAN to the rear control unit, which then activates the ATA [EDW].