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Locking/unlocking, function - GF80.61-P-2008LE

MODEL 216.3, 221.0 /1 with CODE (889) KEYLESS-GO as of model year 2009 /YoM 08 

Function requirements, general 

Locking/unlocking, general 

Locking/unlocking allows the vehicle to be opened and closed.

The following control elements are available:

To lock and unlock (integrated into door handles):

To open trunk:

To lock:

The locking/unlocking functions comprise the following subfunctions:

IMPORTANT The sensor units are switched off when c. 15 is switched on. Activation takes place when circuit 15 is switched off and then a door is opened.

The inner capacitive sensor is switched off after t = 72 h to save the on-board electrical system battery (G1).

After switching off, the vehicle can no longer be unlocked by touching the sensor unit (recognized by the inner capacitive sensor). The sensor unit must be pulled

Function sequence for preadjustment of unlocking mode 

Basically the following types of unlocking are differentiated:

Only the driver door and the fuel filler flap are unlocked by gripping and pulling the sensor unit on the driver door. If the transmitter key is set to selective unlocking and the triggering location for unlocking is not the driver door sensor unit, the vehicle is unlocked globally.

Simultaneously pressing the lock/unlock buttons on the transmitter key for t = 5 s, switches the system between two types of unlocking. The LED on the transmitter key comes on twice to confirm this change.

IMPORTANT Unlocking possibilities:

Locking possibilities:

Function sequence for unlocking 

(example global unlocking at left front door)

If the sensor unit on the driver door is gripped, this is recognized by the inner capacitive sensor. This signal is read in by the KEYLESS-GO control unit (N69/5).

The KEYLESS-GO control then actuates the left door KEYLESS-GO antenna (A2/39) (model 216) or left rear door KEYLESS-GO antenna (A2/39) (model 221), which transmits a wake-up signal to the transmitter key.

In addition the KEYLESS-GO control unit causes the following antennas to transmit a location finding signal:

The locating finding signals are always transmitted by all KEYLESS-GO antennas, regardless of the transmitter key setting (selective/global). The transmitter key transmits its access authorization code and its position to the rear window antenna amplifier module (A2/12), which relays the data to the KEYLESS-GO control unit.

The KEYLESS-GO control unit relays the access authorization code to the EIS control unit (N73) via the interior CAN (CAN B). If the access authorization code is valid, the EIS control unit transmits the command "Open central locking" to the:

They then unlock the following components:

If the driver door sensor unit is pulled within t = 0.5 s after the central locking is unlocked, this is sensed by the Hall sensor in the driver door sensor and transmitted to the KEYLESS-GO control unit. The latter then actuates the left front opening assist motor (A85m2) (model 221) or left opening assist motor (A85m2) (model 216).

When the opening assist motor is actuated, the rotary tumbler "Opens" and the door pops open.

The external operation switch is enabled to unlock the trunk lid by the rear SAM control unit.

IMPORTANT If the transmitter key is set to selective opening and the sensor unit in the driver door is gripped, only the driver door and the tank flap are unlocked.

Function sequence for locking 

The outer capacitive sensor in the sensor unit recognizes if a door handle is gripped from the outside.

The further function sequence is performed analog to global unlocking described previously. However, the opening assist motor is not actuated.

Function sequence for visual feedback (without code (494) USA version) 

After successful locking or unlocking, the turn signal lamps flash as visual feedback.

The function is controlled by the rear SAM control unit, transmitting the turn signal as blinkmaster with the interior CAN:

IMPORTANT For further information on visual feedback see separate function description on exterior lights.

IMPORTANT If a door is still open when locking, there is no visual feedback.

Function sequence for acoustic feedback (as of 1.9.10) 

Select and activate the acoustic feedback in the instrument cluster (A1) via the left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111). The status of the acoustic feedback is transmitted by the instrument cluster via the central CAN (CAN F) to the central gateway control unit (N93) and from there to the front SAM control unit with fuse and relay module (N10/1) via the interior CAN. If the acoustic feedback function is activated and the successful locking and unlocking, an acoustic feedback is output by momentarily actuating the left horn (H2) and right horn (H2/1).

IMPORTANT The left multifunction steering wheel button group and right multifunction steering wheel button group is read via the steering LIN (LIN E1) by the steering column tube module (N80).

If the transmitter key is valid and the acoustic feedback is activated, the EIS control unit transmits the command "Lock or unlock" via the interior CAN to front SAM control unit, which momentarily actuates the horns via the horn relay (N10/1kF).

IMPORTANT If a door is still open when locking, there is no acoustic feedback.

Function sequence for unlocking and opening trunk lid 

The rear SAM control unit recognizes when the trunk lid external operation switch is actuated and signals it to the KEYLESS-GO control unit via interior CAN. The KEYLESS-GO control unit then actuates the trunk KEYLESS-GO antenna, which transmits a wake up signal to the transmitter key.

The transmitter key transmits its access authorization code and position to the KEYLESS-GO control unit via the rear window antenna amplifier module.

The access authorization code is transmitted by the KEYLESS-GO control unit to the EIS control unit via the interior CAN. The access authorization code is valid, the EIS control unit transmits the command "Unlock" to the rear SAM control unit. This signal enables the trunk lid external operation switch. The rear SAM control unit actuates the trunk lid CL motor (M14/7) and opens the trunk lid. The doors remain still unlocked.

IMPORTANT The trunk is locked automatically after closing.

Function sequence for closing and locking trunk lid (model 221 with code (881) Remote trunk closing (RTS), model 216) 

Actuation of the TLC button is recognized by the TLC control unit (N121) and relayed to the KEYLESS-GO control unit via the interior CAN.

The further function sequence is performed analog to unlocking described previously. The trunk lid is closed hydraulically by the TLC control unit only when the vehicle is locked.

IMPORTANT The precise sequence is described in the function "Remote trunk closing (RTC)".

IMPORTANT On vehicles with code (551) Anti-theft alarm (ATA), the anti-theft alarm (ATA) is activated or deactivated with each Model e of locking or unlocking.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for KEYLESS-GO locking and unlocking Model 216 PE80.61-P-2051-97CAA
Model 221 PE80.61-P-2051-97SAA
  Component description for front SAM control unit with fuse and relay module N10/1 GF54.21-P-6070LE
  Component description for rear SAM control unit with fuse and relay module N10/2 GF54.21-P-6030LE
  Component description for left door control unit N69/1
Model 216		 GF72.29-P-4124LA
  Component description for left front door control unit N69/1
Model 221		 GF72.29-P-4141LE
  Component description for right door control unit N69/2
Model 216		 GF72.29-P-4128LA
  Component description for right front door control unit N69/2
Model 221		 GF72.29-P-4142LE
  Rear door control unit, component description N69/3, N69/4
Model 221		 GF72.29-P-6020LE
  Component description for KEYLESS-GO control unit N69/5 GF80.61-P-4204LE 
  EZS control unit, component description N73 GF80.57-P-6003LE 
  Component description for steering column tube module N80 GF54.21-P-6050LE
  TLC control unit, component description N121
Model 221 with code (881) Remote trunk closing (RTC [HDFS])
Model 216		 GF80.20-P-6000LE 
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