LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2011 >> C350 >> Repair and Diagnosis >> Accessories & Equipment >> Anti-Theft Systems >> Anti-Theft/Central Locking System - C63/C350 (204) - 2 Of 2 >> Basic Knowledge >> Activate antitheft alarm system, function (MODEL 204.0/2 with code (551) as of model year 2009; MODEL 204.3, MODEL 204.9) - GF80.50-P-2002CE

Activate antitheft alarm system, function (MODEL 204.0/2 with code (551) as of model year 2009; MODEL 204.3, MODEL 204.9) - GF80.50-P-2002CE

MODEL 204.0/2 with code (551) Anti-theft alarm system (ATA [EDW]) as of model year 2009/YoM 08 

MODEL 204.3 with code (551) Antitheft alarm system (ATA [EDW]) MODEL 204.9 with code (551) Antitheft alarm system (ATA [EDW]) 

Function requirements, general 

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

The ATA is automatically activated with the CL when the vehicle is locked. Then the individual alarm inputs are monitored. When the ATA [EDW] is activated, the anti-theft alarm system indicator lamp (S6/1e2) (up to 28.2.11) flashes permanently in the instrument panel switch group (S6/1) or ATA [EDW] function display (N72/1e2) (as of 1.3.11) in the upper control panel control unit (N72/1).

IMPORTANT On vehicles for Belgium (model 204.0/2 up to 30.9.08) the ATA [EDW] arms automatically without locking the vehicle with the CL.

IMPORTANT It is possible, before locking the CL, to switch off the tow-away protection (without code (494) USA version and without code (460) Canada version and without code (498) Japan version) or the interior protection (with code (882) Interior monitoring (only with ATA [EDW])).

Activation of the ATA [EDW] comprises the following partial functions:

Additional function requirements for switching off tow-away protection (with code (882) Interior monitoring (only with ATA [EDW])) 

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

The tow-away protection is switched off by actuating the tow-away protection button (N70s9) (with code (414) Electric titling/sliding roof in glass version) or tow-away protection button (N70/3s9) (without code (414) Electric titling/sliding roof in glass version) before locking the vehicle with the CL. The rear SAM control unit with fuse and relay module (N10/2) reads in the status of the tow-away protection button via the rear SAM LIN (LIN B4).

Then the rear SAM control unit deactivates the tow-away protection for the following activation of the ATA [EDW].

Deselection of the tow-away protection is confirmed by an LED in the tow-away protection button for approx. t = 2 s after releasing the tow-away protection button.

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

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

The interior protection is switched off by actuating the interior protection button (N70s8) (with code (414) Electric titling/sliding roof in glass version) or interior protection button (N70/3s8) (without code (414) Electric titling/sliding roof in glass version) before locking the vehicle with the CL. The rear SAM control unit reads in the status of the interior protection button via the rear SAM-LIN.

Then the rear SAM control unit deactivates the interior protection for the following activation of the ATA [EDW]. on model 204.2/9, the left rear glass breakage sensor (B39) and rear glass breakage sensor (B39/1) and rear window glass breakage sensor (B39/4) are deactivated in addition.

When the interior protection button is released, deselection is confirmed by an LED flashing in the interior protection button for approx. t = 2 s.

Function sequence for activating ATA [EDW] 

The ATA [EDW] function comprises the following subfunctions:

IMPORTANT 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.

This leads to actuation of an alarm when opening the driver door without previous deactivation of the ATA [EDW].

Function sequence for locking CL with transmitter key 

When the "Lock button on transmitter key" is pressed, a radio signal is sent over the FM, AM and CL antenna amplifier (A2/18 (on model 204.0/3) or via the rear window antenna amplifier 1 (A2/71) (on model 204.2/9) to the rear SAM control unit. This relays the signal to the electronic ignition lock control unit (N73) via the interior CAN (CAN-B).

Parallel to the radio signal, the transmitter sends an infrared signal to the driver front door infrared remote control receiver (A26/1) (precise aiming required). This signal is read in by the left front door control unit (N69/1) and transmitted to the electronic ignition switch control unit via the interior CAN. The access authorization for the transmitter key is checked in both cases by the electronic ignition switch control unit.

If the access authorization is valid, the electronic ignition lock control unit transmits the status "Vehicle locked" via the interior CAN to the rear SAM control unit which activates the ATA.

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

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].

On vehicles with code (889) KEYLESS-GO, the CL can be locked additionally with the transmitter key via the following control elements:

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

After locking the CL, the electronic ignition switch control unit transmits the status "Vehicle locked" with interior CAN to the rear SAM control unit, which then activates the ATA.

Function sequence for automatic activation (model 204.0/2 in Belgium up to 30.9.08) 

When the driver door or trunk lid (model 204.0) or liftgate (model 204.2.) is opened and closed again after removing the transmitter key from the electronic ignition lock control unit, the ATA [EDW] is activated automatically t = 2 min after closing the last door or trunk lid or liftgate regardless of whether or not the vehicle is locked. The interior protection and the tow-away protection are set to the same state as before the last unlocking procedure.

Additional function requirements for activating alarm inputs 

Function sequence for activating alarm inputs 

Activation of the alarm input function comprises the following subfunctions:

Function sequence for monitoring switch 

The status of the following switches is checked cyclically 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 or the liftgate is closed only after the vehicle has been locked), are also armed t = 10 s after closing.

Monitored switches:

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 the liftgate rotary tumbler switch or the status of the Hall sensor of pedestrian protection + engine hood ATA [EDW] switch (with code (U60) pedestrian protection) or the left engine hood contact switch (without code (U60) Pedestrian protection).

The rear SAM control unit in all relevant information and evaluates them 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 (N26/6) (with code (882) Interior protection (only with EDW)) determines a reference position with which the relative vehicle inclination is compared during the active time. 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.

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. If the vehicle 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 (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 204.2/9, the left rear glass breakage sensor and right rear glass breakage sensor and rear window glass breakage sensor are activated in addition.

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.

Activating function sequence for alarm siren (up to 31.5.10 and as of 1.6.10 without code (494) USA version) 

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

IMPORTANT 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 electronic ignition lock control unit). The electronic ignition switch control unit transmits the corresponding signal with interior CAN to the rear control unit, which then activates the ATA [EDW].

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for antitheft alarm system, activation PE80.50-P-2052-97FAB 
  Overview of system components for theft protection and locking GF80.00-P-9999CE