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GF80.20-P-2002CW Operating Central Locking With Transmitter Key, Function



GF80.20-P-2002CW Operating Central Locking With Transmitter Key, Function

General function requirements
^ Circuit 15C Off

Operation with transmitter key, function, general
The central locking can operated with the transmitter key (A8/1).

The operation of the transmitter key comprises the following partial functions:
^ Function sequence for presetting global and selective unlocking
^ Function sequence for locking or unlocking
^ Function sequence for visual feedback
^ Function sequence for remote trunk lid opening (model 204.0)

Function sequence for presetting global and selective unlocking
If the unlock and lock buttons on the transmitter key are pressed simultaneously for 5 seconds, a change between the "global" and "selective" settings takes place. The indicator lamp on the transmitter key comes on for confirmation.

- Global unlocking
The entire vehicle is unlocked by pressing the "Unlock" button on the transmitter key.

- Selective unlocking
Only the driver door and the fuel filler flap are unlocked when the "Unlock" button on the transmitter key is pressed once. The next actuation unlocks the entire vehicle.

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) (on model 204.0) or rear window antenna amplifier 1 (A2/71) (on model 204.2) to the rear SAM control unit with fuse and relay module (N10/2). This relays the signal to the electronic ignition switch control unit (N73) with interior CAN.
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.

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" with the interior CAN to the:
- Front SAM control unit with fuse and relay module (N10/1)
- Rear SAM control unit
- Left front door control unit
- Right front door control unit (N69/2)

They lock or unlock the following components by actuating the:
- Left front door lock (A85)
- Right front door lock (A85/1)
- Left rear door lock (A85/3)
- Right rear door lock (A85/4)
- Tank cap central locking motor (M14/10)

Moreover, the SAM control unit inhibits the opening request from the trunk lid external operation switch (S88/8) (on model 204.0) or tailgate external operation switch (S88/8) (on model 204.2) or enables it.

On vehicles for Great Britain, the left rear door lock is actuated by the left rear door control unit (N69/3) and right rear door lock is actuated by the right rear door control unit (N69/4).

Function sequence for visual feedback
After successfully locking or unlocking, the following components provide visual feedback:
- Left front turn signal lamp (E1e5)
- Right front turn signal lamp (E2e5)
- Left rear turn signal lamp (E3e1)
- Right rear turn signal lamp (E4e1)
- Left outside mirror turn signal lamp (E6/5)
- Right outside mirror turn signal lamp (E6/6)

The function is controlled by the front SAM control unit, transmitting the turn signal as blinkmaster with the interior CAN:
- Locking: flashing 3 times
- Unlocking: flashing once

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

On vehicles with code (494) USA version, an acoustic feedback is output additionally with the alarm siren (H3/1) when locking or unlocking.

Function sequence for remote trunk lid opening
When the button "Trunk lid remote opening" on the transmitter key is actuated, it transmits a radio signal to the rear SAM control unit with the FM, AM and CL antenna amplifier. This relays the signa to the electronic ignition switch control unit with interior CAN. Parallel to the radio signal, an infrared signal is transmitted to the driver front door infrared remote control receiver (precise aiming required).
This signal is read in by the left front door control unit and transmitted to the electronic ignition switch control unit with 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 switch control unit transmits the command "Lock or unlock" to the rear SAM control unit with interior CAN.
This unlocks the rotary tumbler on the trunk lid with trunk lid central locking motor (M14/7).
The trunk lid is opened up to the upper stop by spring force.