Comfort Displays, Function - GF54.30-P-3043KJE

MODEL 453.091/391/491 with CODE K35 (Instrument cluster with monochrome display) 

MODEL 453.091/391/491 with CODE K36 (Instrument cluster with color 8.9 cm (3.5") display) 

Function requirements, general 

• Instrument cluster (A1) activated

Comfort displays in general 

The comfort displays provide a fast overview of the information, which is not required to operate the vehicle.

The comfort display function includes the following subfunctions:

• Function sequence for displaying outside temperature 
• Function sequence for frost warning 
• Function sequence for consumption histogram 
• Function sequence for power flow 
• Function sequence for pre-entry climate control and charging 
• Function sequence for messages and service 
• Function sequence for settings 

Function sequence for displaying outside temperature 

The outside temperature is detected by the outside temperature sensor (M21/2b1). The instrument cluster reads in the signal from the outside temperature sensor directly and uses it to calculate the outside temperature.

The outside temperature is shown in the multifunction display (A1p13) of the instrument cluster in either°C or °F according to the country coding. The following parameters must also be taken into account to determine a correct value of outside temperature:

• Vehicle speed (falsification of value through air stream)

The vehicle speed is calculated on the basis of the wheel speeds.

The Electronic Stability Program control unit (N30/4) sends information on the wheel speeds over the interior CAN (CAN B) to the instrument cluster.

The display range for the outside temperature is between T = -39 and +60°C or between T = -38 and +140 °F, with CODE K35 (Instrument cluster with monochrome display).

The display range for the outside temperature is between T = -40 and +63°C or between T = -40 and +146 °F, with CODE K36 (Instrument cluster with 8.9 cm (3.5") color display).

Function sequence for frost warning 

To determine the temperature value, the instrument cluster uses the outside temperature value obtained directly from the outside temperature sensor.

If the outside temperature drops below the threshold value of T = 3°C, the multifunction display shows an ice crystal symbol as a frost warning. This symbol flashes for t = 60 s to inform the driver that the road may be icy. At the same time the current outside temperature is shown in the multifunction display.

If, once the warning period has expired, the outside temperature is still below the threshold value of 3°C, the ice crystal symbol stays on permanently.

When the outside temperature rises above the threshold value of T = 3°C, the ice crystal symbol in the multifunction display goes out again. The outside temperature shown in the multifunction display remains visible until another display is selected by pressing the left button.

Function sequence for consumption histogram 

The consumption histogram displays the energy consumption or regenerative braking that has occurred in the last 15 min. The information required for this is calculated by the battery management system control unit (N82/2) using the parameters provided by the various consumers. The calculated data is sent via the electric drive CAN (CAN EL) to the electric drive control unit (N127) and from there via the interior CAN to the instrument cluster. This data is shown on the multifunction display as a bar graph.

Function sequence for power flow 

The energy flow display shows both the overall power output and the power output for the auxiliary consumers. The instrument cluster receives the consumption values for both displays from the electric drive control unit via the interior CAN. The electric drive control unit in turn receives the information from the battery management system control unit via the electric drive CAN.

The color of the battery symbol on the multifunction display indicates whether the consumers are absorbing energy (orange battery symbol), energy is being recovered (green battery symbol) or whether energy absorption and regenerative braking are equally high (gray battery symbol).

Function sequence for pre-entry climate control and charging 

The following information is made available in the pre-entry climate control and charging display.

Pre-air conditioning 

For pre-programmed pre-entry climate control, the vehicle must be connected to the power grid via the charging cable; this prevents the high-voltage battery (G5) from discharging. The departure time is set via the instrument cluster. It is possible to save 2 departure times. The pre-entry climate control is activated by selecting the departure time shown with an orange background in the multifunction display using the OK button (S110s7) in the left multifunction steering wheel button group (S110). The instrument cluster is activated approx. 2 hours before the activated departure time. 1 hour before the activated departure time, the pre-entry climate control process is started by the required pre-entry climate control time being determined on the basis of the difference between vehicle interior temperature and vehicle ambient temperature. The target temperature in the vehicle interior is 21°C. During pre-entry climate control, the refrigerant compressor (A9) or the PTC heater (R22/3) and the blower motor (M2) are switched on in order to reach and maintain the target temperature inside the vehicle.

Charging 

The charge indicator in the multifunction display contains the following information:

• Point in time of full charge:

  This information is sent by the battery management system control unit via the electric drive CAN to the electric drive control unit and from there via the interior CAN to the instrument cluster. It is calculated by the battery management system control unit on the basis of the current charge level of the high-voltage battery, the charging current and the current charging capacity.

• Charge level of battery:

  This information is calculated from the current charge level of the high-voltage battery and the max. capacity of the high-voltage battery. The calculated value is sent by the battery management system control unit via the electric drive CAN to the electric drive control unit and sent from there via the interior CAN to the instrument cluster. In the instrument cluster, it is shown in percent in a battery symbol.

• Smart charging:

  With smart charging, the high-voltage battery is charged in a cost-optimized and battery-preserving manner. Smart charging can only be used if it is supported by the electricity provider and the local power supply facility. If smart charging is available, the electricity provider sends a signal to the battery management system control unit via the local power supply facility and the charging cable. From there this signal is sent via the electric drive CAN to the electric drive control unit and forwarded via the interior CAN to the instrument cluster. The multifunction display of the instrument cluster shows the corresponding symbol when smart charging is being used.

• Charging current and charging capacity:

  The charging current and the charging capacity are sent by the battery management system control unit via the electric drive CAN to the electric drive control unit and sent from there via the interior CAN to the instrument cluster.

Function sequence for messages and service 

Stored fault messages can be displayed in the instrument cluster. These fault messages are saved in the fault memory if malfunctions which impair vehicle safety or limit operation of the vehicle occur at components in the vehicle.

The service indicator is a permanently stored value which can be reset via the diagnostic connector (X11/4) using appropriate software after a service deadline. There is a minor service (one screwdriver symbol) and a major service (two screwdriver symbols). These symbols appear on the multifunction display 250 km prior to the service deadline and with the ignition switched on.

Function sequence for settings 

After the instrument cluster has been activated, the settings can be adjusted by using the left multifunction steering wheel button group to navigate through the menu levels on the multifunction display of the instrument cluster.

To change the settings in the menu item "Settings" on the multifunction display of the instrument cluster, the submenu item "Change settings" must be confirmed using the OK button in the left multifunction steering wheel button group.

The following function sequences are submenu items in the "Settings" menu; these submenu items can be called up using the scroll forward button (S110s1) or scroll back button (S110s4) in the left multifunction steering wheel button group.

Function sequence for displaying the time 

The following settings are changed under the submenu item "Time":

• Set time
  • Hours can be changed using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. The selected hour must be confirmed with the OK button in the left multifunction steering wheel button group. The minutes are then activated.
  • Minutes can be changed using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. The selected minute must be confirmed with the OK button in the left multifunction steering wheel button group. The submenu point "Setting time" is then displayed again.
• Time format (12/24 h)
  • The time format can be changed from 12 to 24 hour format and vice versa using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. The selected hour format must be confirmed with the OK button in the left multifunction steering wheel button group; the selected hour format only then becomes visible on the multifunction display of the instrument cluster.

Function sequence for instrument cluster brightness control only for instrument cluster with 8.9 cm (3.5") color display 

The brightness level is adjusted by using the left multifunction steering wheel button group to navigate through the menu levels on the multifunction display of the instrument cluster. Five settings can be selected under the submenu item "Display".

Function sequence for digital speedometer 

The following settings can be changed under the submenu item "Digital speedo":

• "Show additional speedo": To show the additional speedometer on the multifunction display of the instrument cluster, a check mark must be set on the multifunction display of the instrument cluster by pressing the OK button in the left multifunction steering wheel button group. The additional speedometer is only displayed if the check mark is visible on the multifunction display of the instrument cluster.
• "Unit": The unit "km/h" or "mph" can be selected by pressing the OK button in the left multifunction steering wheel button group. After the unit has been selected using the scroll forward button or scroll back button in the left multifunction steering wheel button group, it must be confirmed with the OK button in the left multifunction steering wheel button group. The selected unit only then becomes visible in the digital speedometer.

Function sequence for distance unit 

In the submenu item "Distance unit", the unit "Kilometers" or "Miles" can be selected using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. The selected unit must be confirmed with the OK button in the left multifunction steering wheel button group. The total distance and the trip distance are only then shown in the selected unit on the multifunction display of the instrument cluster.

Function sequence for temperature unit 

In the submenu item "Temperature unit", the unit °C or °F can be selected using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. The selected unit must be confirmed with the OK button in the left multifunction steering wheel button group. The temperature is only then displayed in the selected unit on the multifunction display of the instrument cluster.

Function sequence for radar-supported regenerative braking 

The "radar-supported regenerative braking" function adapts the intensity of regenerative braking of the vehicle to the current traffic situation. The relevant data for the traffic ahead of the vehicle is collected by the distance warning function controller unit with radar sensor (A89) with code 252 (Distance warning function) or by the distance warning function controller unit with active brake intervention (A90) with code 258 (COLLISION PREVENTION ASSIST) and made available via the front end CAN (CAN G). From there this data is, depending on the equipment variant, picked up by the center SAM control unit (N10/10) or by the distance warning function gateway (N93/2) and the required data is forwarded to the instrument cluster.

In the submenu item "Radar-supported regenerative braking", the function can be switched on or off using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. In order to become effective, the selection must be confirmed with the OK button in the left multifunction steering wheel button group.

Function sequence for Active Brake Assist 

With the aid of the radar sensor system, the Active Brake Assist can detect obstacles which have been located ahead of the vehicle for a long period of time. If a risk of collision has been detected, the Active Brake Assist warns the driver visually and acoustically. The adaptive brake assist system then calculates the required brake pressure. If the adaptive brake assist system requests a particularly high brake pressure, preventive measures to protect the vehicle occupants are triggered at the same time.

In the submenu item "Active Brake Assist", the function can be switched on or off using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. In order to become effective, the selection must be confirmed with the OK button in the left multifunction steering wheel button group.

Function sequence for ambiance illumination 

After activating the instrument cluster, the brightness level can be regulated using the left multifunction steering wheel button group through the menu levels in the instrument cluster's multifunction display. Five settings can be selected under the submenu item "Ambiance illumination".

In the submenu item "Ambiance illumination", it is also possible to switch the ambiance illumination on and off using the scroll forward button or scroll back button in the left multifunction steering wheel button group. The selection must be confirmed with the OK button in the left multifunction steering wheel button group.

Tire pressure monitor function sequence 

The tire pressure sensors send the current values to the instrument cluster via the center SAM control unit. If the values are to be reset, proceed as follows.

In the submenu item "Tire pressure monitor", it is also possible to select using the scroll forward button or the scroll back button in the left multifunction steering wheel button group, whether the current tire pressures are to be adopted as new guideline values. Confirm the selection with the OK button in the left multifunction steering wheel button group; the current tire inflation pressures are only then adopted as the guideline value.

Function sequence for language 

In the submenu item "Language", it is possible to set the language in which the displayed messages and instructions are to be shown on the multifunction display of the instrument cluster. To do so, the preferred language must be selected using the scroll forward button or the scroll back button in the left multifunction steering wheel button group. The selection must be confirmed with the OK button in the left multifunction steering wheel button group.

	Electrical function schematic of instrument cluster, comfort display		PE54.30-P-2056-97BBE
	Overview of system components, instrument cluster (IC) component description		GF54.30-P-9996KJE