Activate antitheft alarm system, function

Function requirements, general

 Circuit 15C OFF

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

The ATA is automatically activated with the central locking (CL) when the vehicle is locked. The activated ATA [EDW] is indicated by the ATA [EDW] function indicator (N72/1e3) permanently flashing in the upper control panel control unit (N72/1).

The front SAM control unit (N10/6) transmits the status of the ATA via the interior CAN (CAN B), electronic ignition lock control unit (N73), user interface CAN (CAN HMI), head unit (A26/17) and telematic CAN (CAN A) to audio/COMAND control panel (A40/9) (except code 446 (Touchpad only)) or to the touchpad (A105) (with code 446 (Touchpad only) or code 448 (Touchpad)). The audio/COMAND control panel (except code 446 (Touchpad only)) or touchpad () (with code 446 (Touchpad only) or code 448 (Touchpad)) actuates the ATA function indicator in the upper control panel control unit via UBF-LIN (LIN A3).

 On vehicles for Belgium, the ATA arms automatically without locking the vehicle with the CL.

 Model 213
with code 551 (Anti-theft warning system)
with code 852 (Sensor system for anti-theft alarm system (ATA))
Model 213
with code 551 (Anti-theft warning system)
with code 882 (Interior protection and tow-away protection)
Before locking the CL the tow-away protection or interior protection can be activated or deactivated via a menu in the head unit.

 Model 213
with code 362 (HERMES LTE)
with code 551 (Anti-theft warning system)
with code 852 (Sensor system for anti-theft alarm system (ATA))
Model 213
with code 362 (HERMES LTE)
with code 551 (Anti-theft warning system)
with code 882 (Interior protection and tow-away protection)
When the corresponding service is activated, tow-away protection (and parking damage detection) or interior protection can be activated or deactivated via the customer's mobile phone.

Activation of the ATA comprises the following partial functions:

 Function sequence for activating ATA [EDW]

 Function sequence for switching off tow-away protection and parking damage detection of the ATA (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

 Function sequence for switching off interior protection of the anti-theft alarm system (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

 Function sequence for activating alarm inputs

Function sequence for activating ATA [EDW]

The ATA is activated when the CL is locked. The electronic ignition lock control unit transmits the status of the CL via the interior CAN to the front SAM control unit and overhead control panel control unit (N70). Then the ATA is activated.

 Special case driver door: If the driver door is still open when the CL is locked, it is not locked. After closing the driver door, the left front door control unit (N69/1) sends the status of the driver door via interior CAN to the front SAM control unit. The alarm input is included in the polling cycle. This leads to actuation of an alarm when opening the driver door without previous deactivation of the ATA [EDW].

 Self-activation (only vehicles for Belgium): If, after the engine is shut off, the trunk lid or the liftgate is opened or closed again, the ATA activates by itself 100 s after the last door, the trunk lid or the liftgate are closed again, regardless of the locked vehicle.

Additional function requirements for switching off tow-away protection and parking damage detection of the anti-theft alarm system (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

 ATA [EDW] not yet activated

Function sequence for switching off tow-away protection and parking damage detection of the ATA (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

The tow-away protection is deactivated via a menu in the head unit before locking the vehicle via the CL. With the deselection of the tow-away protection, the parking damage detection (with code 852 (sensor system for anti-theft alarm system (ATA)) or as from December 1, 2017 with code 882 (interior protection and tow-away protection)) is also deactivated.

The head unit transmits the request to deactivate the tow-way protection via user interface CAN, electronic ignition lock control unit and interior CAN to the overhead control panel control unit.

The overhead control panel control unit deactivates the tow-away protection for the subsequent ATA activation and transmits a signal to the status display over:

 Interior CAN, electronic ignition lock control unit and user interface CAN to the instrument cluster (A1).

 Interior CAN, electronic ignition lock control unit and user interface CAN to the head unit. The head unit generates the corresponding image data and sends a switch-on request to the Audio/COMAND display via telematics CAN (A40/8). The image data is transfered via the High-Speed-Video-Link (HSVL) line to the audio/COMAND display.

Additional function requirements for switching off interior protection of the ATA (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

 ATA [EDW] not yet activated

Function sequence for switching off interior protection of the anti-theft alarm system (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

The interior protection is deactivated via a menu in the head unit before locking the vehicle via the CL.

The head unit transmits the request to deactivate the interior protection via user interface CAN, electronic ignition lock control unit and interior CAN to the overhead control panel control unit.

The overhead control panel control unit deactivates the tow-away protection for the subsequent ATA activation and transmits a signal for status display over:

 Interior CAN, electronic ignition lock control unit and user interface CAN to the instrument cluster.

 Interior CAN, electronic ignition lock control unit and user interface CAN to the head unit. The head unit generates the corresponding image data and sends a switch-on request to the Audio/COMAND display via telematics CAN. The image data is transmitted via HSVL line to the audio/COMAND display.

Additional function requirements for activating alarm inputs

 ATA [EDW] activated

Function sequence for activating alarm inputs

Activating alarm input partial function comprises the following subfunctions:

 Function sequence for monitoring switch

 Function sequence for activating tow-away protection and parking damage detection (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

 Function sequence for activating interior protection (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

 Function sequence for activating alarm siren (H3/1) (with code 882 (Interior protection and tow-away protection))

Function sequence for monitoring switch

The status (open or closed) is checked cyclically for the following switches every 200 ms:

 Left front door main catch microswitch (A85s2) in left front door lock (A85)

 Right front door main catch microswitch (A85/1s2) in right front door lock (A85/1)

 Left rear door main catch microswitch (A85/3s2) in left rear door lock (A85/3)

 Right rear door main catch microswitch (A85/4s2) in right rear door lock (A85/4)

 Trunk lid/liftgate lock main catch switch (A85/5s1) in trunk lid/liftgate lock (A85/5)

 Left engine hood contact switch (S62/43)

The left front door control unit reads in the status of the left front door main catch microswitch directly and sends it via interior CAN to the front SAM control unit. The right front door control unit (N69/2) reads in the status of the right front door main catch microswitch directly and sends it to the SAM control unit via interior CAN.

The left rear door control unit (N69/3) directly reads in the status of the left rear door main catch microswitch and sends it via interior CAN to the front SAM control unit. The right rear door control unit (N69/4) directly reads in the status of the right rear door main catch microswitch and sends it via interior CAN to the front SAM control unit.

The rear SAM control unit (N10/8) reads in the status of the trunk lid/liftgate lock main catch switch directly and sends this via interior CAN to the front SAM control unit.

The front SAM control unit reads in the status of the left engine hood contact switch directly and evaluates the status of all other alarm inputs.

Alarm inputs, set only later to the non-actuated state (e.g. if the trunk lid or liftgate is closed only after the vehicle has been locked) are also ready for alarm 10 s after closing.

Function sequence for activating tow-away protection and parking damage detection (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

The tow-away protection and parking damage detection (with code 852 (sensor system for anti-theft alarm system (ATA)) or as from December 1, 2017 with code 882 (interior protection and tow-away protection)) are (if not previously deselected for the next lock) activated 60 s after locking the CL and closing the last door and the trunk lid or the liftgate.

For the tow-away protection, the inclination sensor in the overhead control panel control unit determines a reference position with which the relative vehicle inclination is compared during the active time. Determination of the reference position takes approx. 10 to 15 s. An alarm can only be triggered approx. 60 s after the ATA is armed, at the earliest.

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 inclination sensor.

For parking damage detection, the vehicle movement is evaluated via the inclination sensor. If a physical shock that may have caused parking damage is detected, a corresponding message is sent.

If the 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 overhead control panel control unit.

Function sequence for activating interior protection (with code 852 (Sensor system for anti-theft alarm system) or with code 882 (Interior protection and tow-away protection))

The interior protection is activated 10 s after the CL is locked and the last door is closed and the trunk lid or liftgate is activated (if not previously deselected for the next locking operation). After another 10 s is required before the interior protection is ready for an alarm, because it is necessary for the overhead control panel control unit to first calibrate the vehicle passenger compartment.

On model 213.2, , the signals of the following sensors are evaluated in addition to the interior protection:

 Left rear window glass breakage sensor (B39)

 Right rear window glass breakage sensor (B39/1)

 Rear window glass breakage sensor (B39/4)

The status of the glass breakage sensor is read in directly by the overhead control panel control unit.

If the glass breakage 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 overhead control panel control unit.

Function sequence for activating alarm siren (with code 882 (Interior protection and tow-away protection))

The alarm siren is armed together with the ATA and checked cyclically approx. every 600 ms from the overhead control panel control unit via the alarm system LIN (LIN B14).

 Deactivating ATA: The ATA is completely deactivated by opening the CL with the transmitter key (A8/1) via radio or by actuating the KEYLESS-GO start/stop button (S2/3). The electronic ignition lock control unit sends the corresponding signal via interior CAN to the front SAM control unit, which then deactivates the ATA [ATA].