GF54.30-P-3044LEH Trip Computer, Function

GF54.30-P-3044LEH Trip Computer, 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).

Trip computer (TRIP) position in general
The trip computer provides data and information on average fuel consumption, trip time, average speed, travel distance and remaining range. The information is shown in the multifunction display (A1p13) in the instrument cluster.

The trip computer provides the following display screens:
- "AFTER START" (short-distance memory)
- "After reset" (long-distance memory)

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 following content can be shown on the trip computer:
- Selected display screen "After start" or "After reset"
- Travel distance driven "After start" or "After reset"
- Time passed "After start" or "After reset"
- Average transportation speed
- Average fuel consumption

The corresponding display screen can be selected by scrolling with the scroll forward and back button (S110s1) and then selecting with the system selection button (S110s3).
The steering column tube module (N80) reads in the corresponding selection via the steering LIN (LIN E1) and transmits this to the instrument cluster via the interior CAN (CAN B), central gateway control unit and central CAN.
The trip computer is comprised of the following subfunctions:
^ Display of travel distance function sequence
^ Function sequence for the time display
^ Function sequence for the average speed display
^ Function sequence for displaying average and present consumption
^ Function sequence for remaining distance display
^ Function sequence for reset display

Display of travel distance function sequence
The travel distance is calculated in the instrument cluster from 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 and calculates the travel distance. The travel distance "After start" is displayed in a range of 0 to 9999 km. An automatic reset is performed following a travel distance "After start" overflow.

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.

The "After reset" travel distance display is shown in a range of 0 to 99 999 km. An automatic reset takes place at a value of the travel distance "After reset" of more than 100 000 km.
Depending on the setting in the instrument cluster and the national version code, the travel distance is displayed in:
- Kilometers (e.g Economic Commission for Europe (ECE))
- Miles (e.g. USA)

When changing over from kilometers to miles a changeover from liters to gallons also takes place automatically.

Function sequence for the time display
For circuit 15 ON a time counter in the instrument cluster adds up the time "AFTER START" or "AFTER RESET". The display covers a The "After reset" time is range of 0 to 999 h and 59 minutes. calculated in the same manner as for "After start", however the display covers 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. Depending on the setting (kilometers/miles) and national version code, the average speed display is shown in:
- km/h (kilometers per hour)
- mph (miles per hour)

Function sequence for displaying average and present consumption
The trip computer calculates the fuel consumption using the following information:
- Fuel consumption signal from ME-SFI [ME] control unit (N3/10)
- Travel distance covered "After start" or "After reset"

Depending on the unit 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)
- km/l (kilometers per liter)

The ME-SFI control unit transmits the relevant information to the instrument cluster via the chassis CAN, central gateway control unit and central CAN.

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 current tank contents are recorded by the fuel level sensor, left tank half (B4/1) and fuel level sensor, right tank half (B4/2). The rear SAM control unit with fuse and relay module (N10/2) reads in the signals from the fuel level indicator sensors and transmits them via the interior CAN, central gateway control unit and central CAN to the instrument cluster. The average fuel consumption is gathered from the short-distance memory or longdistance memory.

Function sequence for reset display
The trip computer is reset by pressing the OK button (S110s6) in the left multifunction steering wheel button group (S110). Here, the reset is only carried out for the currently displayed information.