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

MODEL 164.1 as of model year 2009 with CODE 889 (Keyless Go) 

MODEL 164.8, 251.0/1 as of model year 2009 with CODE 889 (Keyless Go) 

Function requirements, general 

IMPORTANT The EZS control unit (N73) sends the status of circuit 15 via interior CAN (CAN B) to the KEYLESS-GO control unit (N69/5).

Locking/unlocking, general 

Locking/unlocking allows the vehicle to be opened and closed. The following control elements are available:

The locking/unlocking function comprises the following partial functions:

IMPORTANT All sensors in the KEYLESS GO door handles are switched off when switching on circuit 15. The sensors are activated when the circuit 15 is switched off and a door is opened.

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

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

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

Basically the following types of unlocking are differentiated:

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 to confirm this change.

Control points: 

Function sequence for position determination of transmitter key and inquiry for access authorization 

To ensure that the locking/unlocking function can be realized reliably and securely, it is necessary to determine the position of the transmitter key and to authorize it.

Position determination is activated by actuating the following control elements:

The KEYLESS-GO control unit directly reads in the signals from the capacitive sensors. The rear SAM control unit (N10/8) directly reads in the status of the rear-end door handle switch and spare wheel holder control unit (with code (849) Spare wheel holder/spare wheel) and transmits it to the KEYLESS-GO control u nit via the interior CAN.

Then the KEYLESS-GO control unit transmits the coded requests to the transmitter key via the following antennas:

The transmitter key decodes these requests and transmits the corresponding coded responses via the roof antenna module (A2/93) to the KEYLESS-GO control unit. The KEYLESS-GO control unit receives the responses from the transmitter key and evaluates them. If the evaluation is positive, the KEYLESS-GO control unit authorizes the transmitter key and transmits the access authorization code to the EZS control unit via the interior CAN.

Function sequence for unlocking 

The following example describes unlocking the left front KEYLESS-GO door handle control point (presetting "global opening").

The inner capacitive sensor recognizes if the left front KEYLESS GO door handle is gripped. The KEYLESS-GO control unit reads in the signal from the capacitive sensors and starts an inquiry for the access authorization.

IMPORTANT Detailed information on the signal curve is given in the chapter "Position determination for transmitter key and inquiry for access authorization".

If the access authorization is valid, the EZS control unit transmits the request "Open central locking (CL)" via the interior CAN to the following control units:

The front SAM control unit directly actuates the left rear door CL motor (M14/8).

The rear SAM control unit directly actuates the right rear door CL motor (M14/9) and the fuel filler flap CL motor (M14/10) and enables the rear-end door handle switch to unlock the liftgate and the spare wheel carrier control button to unlock the spare tire carrier (with code (849) Spare wheel holder/spare wheel).

The right front door control unit actuates the right front door CL motor (M14/6).

The right front door control unit directly actuates the right front door CL motor (M14/5).

Function sequence for locking 

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

Additional function requirements for opening liftgate 

IMPORTANT The rear SAM control unit directly reads in the status of the spare tire carrier switch (with code (849) Spare wheel holder/spare wheel).

All other function sequences are performed as described previously for "Unlocking" function sequence.

IMPORTANT If one of the doors is opened, the vehicle is not locked.

Function sequence for opening liftgate 

The rear SAM control units directly reads in the status of the rear end door handle switch and transmits it to the KEYLESS-GO control unit via the interior CAN. The KEYLESS-GO control units stars the inquiry for the access authorization.

IMPORTANT Detailed information on the signal curve is given in the chapter "Position determination for transmitter key and inquiry for access authorization".

If the access authorization is valid, the EZS control unit sends the request "Open liftgate" to the rear SAM control unit via the interior CAN. This enables the signal for the rear-end door handle switch and then actuates the rear-end door locking unit (A72).

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

After the CL is locked or unlocked successfully, a visual feedback is output via the turn signals.

The EZS control unit transmits the request "Lock" or "Unlock" to the rear SAM control unit via the interior CAN. The rear SAM control unit then activates the hazard warning flasher function. All turn signals are actuated synchronously on the vehicle.

Three flashing cycles are output when locking.

One flashing cycle is output when unlocking.

IMPORTANT Detailed information on performing the hazard warning flasher function is included in the function description "Exterior lights, function" in the partial function "Turn signal light actuation, function".

Function sequence for acoustic locking feedback (as of 1.7.11) 

The acoustic locking feedback can be selected and activated in the instrument cluster (A1) using the left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111). The control signals from the multifunction steering wheel button groups are read in directly by the steering wheel electronics (N135) and transmitted via the steering LIN (LIN E1) to the steering column tube module control unit (N80). The steering column tube module control unit forwards the control signals via the engine compartment CAN (CAN C) to the instrument cluster.

The instrument cluster transmits the status of the acoustic locking feedback via the body CAN to the front SAM control unit.

If the function of acoustic locking feedback has been activated, after successful locking or unlocking an acoustic feedback takes place after brief actuation of the left horn (H2) and right horn (H2/1).

If the transmitter key is valid and the acoustic feedback is activated, the EZS control unit transmits the request "Lock" or "Unlock" via the interior 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 (F58kF).

Number of acoustic signals:

Locking: three signals

Unlocking: one signal

IMPORTANT If a door or liftgate is still opened when locking, no acoustic locking feedback takes place.

Additional function requirements for unlocking spare wheel carrier (with code (849) Spare tire holder/spare tire) 

IMPORTANT The rear SAM control unit reads in the status of the spare wheel carrier switch locked switch directly.

Function sequence for unlocking spare tire carrier (with code (849) Spare tire holder/spare tire) 

The rear SAM control unit directly reads in the status of the spare wheel carrier control unit and transmits it to the KEYLESS-GO control unit via the interior CAN. The KEYLESS-GO control units stars the inquiry for the access authorization.

IMPORTANT Detailed information on the signal curve is given in the chapter "Position determination for transmitter key and inquiry for access authorization".

If the access authorization is valid, the EZS control unit sends the request "Open central locking" to the rear SAM control unit via the interior CAN. This enables the signal for the spare tire carrier control button and then actuates the spare tire carrier CL motor (M14/13).

IMPORTANT On vehicles with code (890) EASY PACK liftgate, the liftgate can be closed via the RWT button (S62/26) when the spare wheel carrier is opened and the vehicle can then be locked. The rear-end door control unit button is read in by the rear-end door closing system control unit (N121/1). The rear-end door closing system control unit transmits the status of the rear-end door control unit via the interior CAN.

  Electrical function schematic for KEYLESS GO locking and unlocking MODEL 164.1 as of model year 2009 with CODE 889 (Keyless Go) MODEL 164.8 as of model year 2009 with CODE 889 (Keyless Go) PE80.61-P-2051-97MAA
MODEL 251.0/1 as of model year 2009 with CODE 889 (Keyless Go) PE80.61-P-2051-97RAA
  Survey of Keyless Go system components, component description   GF80.61-P-9997GM 
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