GF54.30-P-3041LEH Display Operating Conditions, Function
GF54.30-P-3041LEH Display Operating Conditions, Function
General function requirements
^ Circuit 15 ON
The EZS control unit (N73) transmits the status of circuit 15 over the chassis CAN (CAN E), central gateway control unit (N93) and central CAN (CAN F) to the instrument cluster (A1).
Display operating conditions, general
The operating conditions display provides the driver with permanent information about the current operating conditions of the vehicle.
The Display operating conditions function is comprised of the following partial functions:
^ Function sequence for displaying charge level of high voltage battery (A100g1)
^ Speed display function sequence
^ Display of engine speed function sequence
^ Display of coolant temperature function sequence
^ Display of fuel quantity function sequence
^ Display of travel distance function sequence
^ Function sequence, gear display and transmission mode display
Function sequence for displaying charge level of high-voltage battery
The charge level of the high-voltage battery is shown in the form of a battery symbol with the power level shown as a percentage in the multifunction display (A1p13).
The display is called up by the following selection:
- Select "Trip" menu using system selection button (S110s3)
- Select hybrid display by scrolling using scroll forward and back button (S110s1)
The charge level of the high-voltage battery is also shown on the COMAND display (A40/8) (without code (867) SPLIT VIEW) or in SPLIT VIEW display (A40/10) (with code (867) SPLIT VIEW). The power level is shown here as a percentage too. The hybrid drive energy flow is also denoted by arrows.
The data required for display are sent by the battery management system control unit (N82/2) over the drive train sensor CAN (CAN I), ME-SFI [ME] control unit (N3/10), chassis CAN, central gateway control unit and the central CAN to the instrument cluster and to the COMAND display or the SPLIT VIEW display.
The instrument cluster and the COMAND display or the SPLIT VIEW display receive the data and evaluate them accordingly for displaying.
Additional function requirements for vehicle speed display
^ Vehicle speed v > 0 km/h
Speed display function sequence
The vehicle speed is calculated on the basis of the wheel speeds. The wheel speeds are recorded by the following components:
- Left front rpm sensor (L6/1)
- Right front rpm sensor (L6/2)
- Left rear rpm sensor (L6/3)
- Right rear rpm sensor (L6/4)
The regenerative braking system control unit (N30/6) reads in the signals from the rpm sensors and transmits these to the instrument cluster via the chassis CAN, central gateway control unit and central CAN.
The instrument cluster receives the signals from the rpm sensors, calculates the current vehicle speed and actuates the electronic speedometer (A1p8) by means of a stepper motor.
A digital speedometer can be displayed in the "Trip" menu.
Additional function requirements for display of engine speed
^ Circuit 61 ON status
Display of engine speed function sequence
The engine speed is recorded by the camshaft Hall sensor (B70). The ME-SFI control unit reads in the signals from the crankshaft Hall sensor, calculates the engine speed from these and transmits a corresponding value to the instrument cluster via the chassis CAN, central gateway control unit and central CAN. The instrument cluster receives the value for the engine speed and actuates the tachometer (A1p5) accordingly by way of a stepper motor.
Display of coolant temperature function sequence
The coolant temperature is recorded by the coolant temperature sensor (B11/4). The ME-SFI control unit reads in the signal from the coolant temperature sensor, calculates the coolant temperature from this and transmits the corresponding value to the instrument cluster via the chassis CAN, central gateway control unit and central CAN. The instrument cluster receives the value for the coolant temperature and actuates the coolant temperature display (A1p1) accordingly by way of a stepper motor.
Display of fuel quantity function sequence
The fuel level indicator sensor, left tank half (B4/1) and fuel level indicator sensor, right tank half (B4/2) record the fill level of the fuel tank. The rear SAM control unit with fuse and relay module (N10/2) reads in the signals from the fuel level indicator sensor and transmits these to the instrument cluster via the interior CAN (CAN B), central gateway control unit and central CAN.
The instrument cluster receives the signals from the fuel level indicator sensor, evaluates these and actuates the fuel level and reserve indicator (A1p2) accordingly by way of a stepper motor. If the reserve range has been reached (approx. 12.5 % of maximum tank capacity), the instrument cluster actuates the fuel reserve warning lamp (A1e4). The reserve range is defined by comparing the measured fill level against a stored tank characteristic. If the reserve range drops to approx. 50 %, a gas station symbol in the form of a gasoline pump is shown in the Range menu instead of the distance reading.
Display characteristics of fuel level indicator:
- After switching on circuit 15, the current fill level is displayed. In the process, the pointer runs up without being buffered.
- While driving, the display is updated via a dampening.
- When circuit 15 is switched off, the pointer of the fuel level indicator moves back to zero.
A fuel level indicator sensor which is jammed tight is detected by comparing the change in fill level of the fuel tank with the calculated composite mileage.
If the fill level decreases quicker over a particular stretch than is technically possible due to the composite mileage, a defective fuel level indicator sensor is detected and a corresponding message issued via the multifunction display.
Display of travel distance function sequence
The travel distance display function is made up of the following subfunctions:
^ Determination of travel distance function sequence
^ Display of main odometer reading function sequence
^ Display of trip distance function sequence
^ Storage of counter readings function sequence
Determination of travel distance function sequence
The instrument cluster calculates the travel distance from the signals received from the rpm sensors taking the tire circumference into consideration.
The coding of the tire size is made via the diagnosis tester.
Display of main odometer reading function sequence
The main odometer reading display is shown in the multifunction display. The maximum displayed counter reading of the main odometer reading is 999,999. This is followed by an overflow to 0. The actual kilometer reading however continues to be counted internally in the instrument cluster.
Display of trip distance function sequence
The trip distance display is shown in the multifunction display. The maximum displayed counter reading of the trip distance is 9999,9. If this value is reached, an overflow back to 0 takes place.
Storage of counter readings function sequence
The main odometer reading is saved continuously to the nonvolatile part of the instrument cluster's internal memory. This memory guarantees the retention of the counter reading for at least five years even when the on-board electrical system battery (G1) is disconnected. The current reading of the trip odometer is likewise stored in the nonvolatile memory of the instrument cluster.
Function sequence, gear display and transmission mode display
The intelligent servo module for DIRECT SELECT transmits information on the current transmission selector lever position for the gear indicatorA80 and the fully integrated transmission control unit (VGS) (Y3/8n4) transmits the status of the selected transmission mode for transmission mode display to the instrument cluster via the drive train CAN (CAN C), ME-SFI [ME] control unit, chassis CAN, central gateway control unit and central CAN.
The instrument cluster receives this information and actuates the gear indicator (A1p12) in the multifunction display. The gear range currently engaged and the selected transmission mode is shown in the gear indicator.
