Trip Computer, Function - GF54.30-P-3044FR
Model 257, 290
up to model year 2021
Function requirements, general
- Circuit 15 ON:
The electronic ignition lock control unit (N73) transmits the status of circuit 15 via the user interface CAN (CAN HMI) to the instrument cluster (A1).
Trip computer, function, general
The trip computer calculates information on average fuel consumption, journey time, average speed, travel distance and remaining range.
The trip computer provides the following display screens:
- "After start" (short-distance memory)
- "After reset" (long-distance memory)
- "Present consumption"
The information displayed refers to the point in time of the last reset of the short-distance memory ("After start") or of the long-distance memory ("After reset").
The "After start" or "After reset" information is shown on the instrument cluster as follows:
- Distance traveled
- Time elapsed
- Average consumption
- Average transportation speed
The trip computer includes the following subfunctions:
- Function sequence, travel distance display after start/after reset
- Function sequence, time display after start/after reset
- Function sequence for the average speed display
- Function sequence for display of present consumption and composite mileage
- Function sequence for displaying ECO Score (driving style analysis)
- Function sequence for remaining distance display
- Function sequence for display reset
Function sequence, travel distance display after start/after reset
The travel distance is calculated on the basis of the wheel speeds.
The Electronic Stability Program control unit (N30/4) transmits the information about the wheel speeds via the chassis FlexRay (Flex E), the electronic ignition lock control unit and the user interface CAN to the instrument cluster. The instrument cluster calculates the traveled distance from the wheel speeds. The "After start" travel distance is shown in a range from 0 to 9999 km.
If a period of more than t = 4 h lies between the time when circuit 15 is switched off and then switched on again, then the "After start" odometer is automatically reset to 0.
Distance units are changed in the "settings" menu in the "instrument cluster" submenu. The distance unit can be changed from kilometers to miles in the "speedometer/travel distance display unit" display window. The "After reset" distance is calculated as for the "After start" distance, although the "After reset" distance is shown in a range of 0 to 9999 km.
Depending on the setting in the instrument cluster and coding of the national version of the instrument cluster, the travel distance is displayed in:
- Kilometers (e.g Economic Commission for Europe (ECE), Japan)
- Miles, (e.g. USA, Australia)
When kilometers are switched over to miles, liters are switched over to gallons automatically.
Function sequence, time display after start/after reset
With circuit 15 ON, the "After start" time is incremented. Die "After start" time is shown in a range of 0 to 999 h and 59 min.
The "After reset" time is determined as for the "After start" time, although the "After reset" time is shown in a range of 0 to 9999 h and 59 minutes.
Function sequence for the average speed display
The trip computer calculates the average speed from the ratio between the travel distance driven and the time passed (trip time) since the last reset of the short-distance memory or long-distance memory. The travel distance is calculated in the instrument cluster from the wheel speeds.
The Electronic Stability Program control unit sends information on the wheel speeds over the suspension FlexRay, electronic ignition lock control unit and the user interface CAN to the instrument cluster.
Depending on the setting (kilometers/miles) and the national variant coding of the instrument cluster the average speed is displayed in:
- km/h (kilometers per hour)
- mph (miles per hour)
Function sequence for display of present consumption and composite mileage
The CDI control unit (N3/9) (with diesel engine) or the ME-SFI [ME] control unit (N3/10) (with gasoline engine) sends the consumption signal over the engine CAN (CAN C), powertrain control unit (N127), chassis FlexRay, electronic ignition lock control unit and the user interface CAN to the instrument cluster.
Depending on the setting (kilometers/miles) and the national variant coding of the instrument cluster the fuel consumption is displayed in:
- l/100 km (Liters per 100 kilometers)
- mpg (miles per gallon) or
- km/l (kilometers per liter)
The present consumption is displayed together with the range. The display is in the form of a bar.
Function sequence for displaying ECO Score (driving style analysis)
Shown on model 257, German system language
The "ECO Score" display graphically displays the individual handling characteristics in the form of a pie chart.
The following information is displayed:
- Acceleration characteristic
- Uniform driving
- Rolling out
- Range gained in additional kilometers after start
- "Glow", when all segments are filled
The data required for evaluation purposes are sent by the CDI control unit or the ME-SFI [ME] control unit over the engine CAN, powertrain control unit, chassis FlexRay, electronic ignition lock control unit and the user interface CAN to the instrument cluster.
Function sequence for remaining distance display
The trip computer determines the expected range from the ratio between the current tank capacity and the average fuel consumption.
The fuel system control unit (N118) sends information on the fill level of the fuel tank via the drive train CAN (CAN C1), powertrain control unit, chassis FlexRay, electronic ignition lock control unit and user interface CAN to the instrument cluster.
Function sequence for display reset
The displayed values can be reset to 0 in the "Reset values" menu. The reset is only carried out for the currently displayed information (After start/reset).
The request over the instrument cluster multifunction steering wheel button group (S163/1) is read in by the steering wheel electronics (N135) and sent over the steering wheel CAN (CAN LR) to the steering column tube module control unit (N80). The steering column tube module control unit sends this request via chassis FlexRay, the electronic ignition lock control unit and user interface CAN to the instrument cluster.
| Electrical function schematic, instrument cluster trip computer | PE54.30-P-2057-97XBA | ||
| Overview of system components, instrument cluster (IC) component description | GF54.30-P-9996FR |