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Operating central locking with transmitter key, function - GF80.20-P-2002CE

MODEL 204.0/2 as of model year 2009/YoM 08 

MODEL 204.3 

MODEL 204.9 

Function requirements, general 

Central locking (CL), operation with transmitter key (A8/1) general 

The central locking is operated via the transmitter key and enables the vehicle to be locked or unlocked centrally.

IMPORTANT As an alternative to the transmitter key the locking or unlocking of the doors is possible via the emergency key integrated in the transmitter key.

The CL operating function with remote control key comprises the following partial functions:

Function sequence for presetting global or selective unlocking 

Simultaneously pressing the unlock/lock buttons on the transmitter key for t = 5 s, switches the system between global and selective unlocking.

The indicator lamp on the transmitter key comes on for confirmation.

Function sequence for locking or unlocking 

When the "Lock" or "Unlock" buttons on the transmitter key are actuated, it transmits a radio signal with the FM, AM and CL antenna amplifier (A2/18) (model 204.0/3) or rear window antenna amplifier 1 (A2/71) (model 204.2/9) to the rear SAM control unit with fuse and relay module (N10/2). It relays a signal via the interior CAN (CAN B) to the electronic ignition lock control unit (N73).

Parallel to the radio signal, an infrared signal is transmitted 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 with interior CAN.

IMPORTANT The infrared and radio signals contain the same information (redundant). The first signal received always has priority.

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 switch control unit transmits the command "Lock or unlock" via the interior CAN to the following control units:

The left front door control unit locks or unlocks the left front door lock (A85) via the left front door central locking motor (A85m1). The right front door control unit locks or unlocks the right front door lock (A85/1) via the right front door central locking motor (A85/1m1)

Vehicles up to 30.11.09:

The front SAM control unit locks or unlocks the left rear door lock (A85/3) over the left rear door central locking motor (A85/3m1) and the right rear door lock (A85/4) over the right rear door central locking motor (A85/4m1).

Model 204.0/2/9 as of 1.12.09:

The left rear door control unit locks or unlocks the left rear door lock over the left rear door central locking motor.

The right rear door control unit locks or unlocks the right rear door lock over the right rear door central locking motor.

The rear SAM control unit locks or unlocks the tank cap over the tank cap central locking motor (M14/10).

In addition the rear SAM control unit blocks the opening request of the trunk lid external operation switch (S88/8) (model 204.0/3) or the liftgate external operation switch (S88/8) (model 204.2/9) or it enables the request accordingly.

The status of the vehicle doors as well as the trunk lid or lift gate is sensed by the following switches:

The corresponding door, trunk lid or liftgate is locked or unlocked, depending on the status (open or closed).

On model 204.0/2/3 for Great Britain, the following components are actuated in addition:

IMPORTANT Vehicles with code (551) Anti-theft alarm system (ATA [EDW]): If the driver door in the locked vehicle is opened mechanically with the emergency key, the anti-theft alarm system (ATA) triggers an alarm.

Function sequence for visual locking feedback 

After successful locking or unlocking the CL, a visual locking feedback takes place via the following components:

The function is controlled by the SAM front control unit, transmitting the corresponding flasher frequency as blinkmaster via the interior CAN:

Number of visual signals:

IMPORTANT If, after locking, a door, the trunk lid (model 204.0/3) or liftgate (model 204.2/9) is still open, these is no visual locking feedback.

IMPORTANT Detailed information on turn signal light actuation is described in the document "Turn signal light actuation function".

Function sequence for acoustic locking feedback (as of 1.6.10) 

The acoustic locking feedback can be selected and activated in the IC (A1) via the left multifunction steering wheel button group (S110).

The instrument cluster reads in the control signals from the left multifunction steering wheel button group via the following path:

The instrument cluster transmits the status of the acoustic locking feedback via the body CAN to the front SAM control unit. If the acoustic locking feedback function is activated, the left horn (H2) and right horn (H2/1) are actuated momentarily after successful locking/unlocking.

If the transmitter key is valid and the acoustic feedback is activated, the electronic ignition lock control unit transmits the command "Lock or unlock" via the body CAN to the front SAM control unit. As a result of this the front SAM control unit actuates the horns briefly via the horns relay (N10/1kO).

Number of acoustic signals:

IMPORTANT If, after locking, a door, the trunk lid (model 204.0/3) or liftgate (model 204.2/9) is still open, there is no acoustic locking feedback.

IMPORTANT On vehicles up to 31.5.10 with code (494) USA version, the acoustic locking feedback via the horns replaces the acoustic locking feedback via the alarm siren (H3/1).

Function sequence for trunk lid remote opening (model 204.0/3) or liftgate remote opening (model 204.2/9 with code (890) EASY-PACK liftgate) 

When the trunk lid/liftgate remote opening button the transmitter key is pressed, it transmits a radio signal to rear SAM control unit via the FM, AM and ZV antenna amplifier (model 204.0/3) or rear window antenna amplifier 1 (model 204.2/9). This relays the signal to the electronic ignition switch control unit via the interior CAN. The electronic ignition lock control unit checks the access authorization for the transmitter key.

If the access authorization is valid, the electronic ignition switch control unit transmits the command "Lock or unlock" to the rear SAM control unit via the interior CAN.

On model 204.0/3, the trunk lid rotary tumbler is unlocked by the trunk lid central locking motor (M14/7). The trunk lid is then opened mechanically by spring force as far as the upper stop.

On model 204.2/9, the trunk lid rotary tumbler is unlocked by the trunk lid central locking motor (M14/7). The liftgate is then opened automatically.

IMPORTANT Detailed information on liftgate control is given in the separate document rear door remote actuation, function".

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for central locking, operation with transmitter key PE80.20-P-2052-97FAB 
REFER TO SYSTEM WIRING DIAGRAMS Overview of system components for theft protection and locking GF80.00-P-9999CE 
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