Driver/Vehicle Information Display: Description and Operation
Information and Message Center
COMPONENT LOCATION
INTRODUCTION
The message center is a Liquid Crystal Display (LCD) located in a central position in the instrument cluster.
The message center displays system information, vehicle status and trip computer information to the driver. The message center is controlled by the instrument cluster and displays system information using CAN and hard wired signals received from other vehicle system control modules.
MESSAGE CENTER
The message center LCD display has a viewable area of 240 pixels horizontal and 315 pixels vertical. It is divided into five information display zones as follows, starting from the top:
- Transmission position
- Set speed
- Warning /message display
- Odometer/Trip computer information
- Fuel level.
The message center is active at all times when the ignition is on and can also be active when the ignition is off, dependant on the information to be displayed.
The message center LCD is displayed at its full brightness when the ignition is on and the exterior lights are off. If the exterior lights have been activated by the AUTO windshield wipers feature, the illumination will remain at full brightness. If the exterior lights are on in any position other than AUTO, then the LCD will be illuminated at a brightness controlled by the illumination dimmer which is located in the auxiliary lighting switch.
If more than one message is active, each message is displayed in turn in the order of priority. Once all messages have been displayed, they are again displayed in turn for 2 seconds each. Warning messages can be displayed when the ignition is in convenience mode which is the initial ignition state when a door is opened.
Message Priority
Messages are assigned priorities which are defined by the effect on driving safety and functional ability of the vehicle. When new messages are displayed they may be accompanied by a chime from the instrument cluster sounder.
A new message will be displayed immediately, providing the currently displayed message (if there is one) has been displayed for at least 4 seconds. A warning indicator will be activated simultaneously with the message being displayed. If more than one fault warning message is being displayed, the messages will cycle, in priority order, with each message being displayed for 2 seconds.
INFORMATION DISPLAY
Transmission Display
The transmission display is located in the upper section of the LCD. The transmission position information is sent from the Transmission Control Module (TCM) in a high speed CAN message to the instrument cluster.
The transmission has three modes of operation:
- Conventional automatic operation (selector in 'D' position)
- Sport automatic operation (selector lever in 'S' position)
- Manual gear operation - Jaguar Sequential Shift
The following table shows the selector lever position and the highlighted indication displayed in the transmission display.
The following table shows the Jaguar Sequential Shift display. Selections are made using the steering wheel mounted paddle switches.
The transmission may inhibit a requested up or down shift if the requested gear is outside the normal engine speed operating range. If this occurs, the transmission display will briefly display the gear requested by the driver but will then change to display the actual gear selection.
Set Speed Display
The following table shows the possible messages which can be displayed, other visual or audible warnings and a description of the message.
Warning/Message Display
Warning and information messages are displayed in the central area of the LCD. When no messages are required, an analogue clock is present on the display.
The message display language can be changed by the driver using a selection menu on the Touch Screen Display (TSD).
The following table shows the possible messages which can be displayed, other visual or audible warnings and a description of the message.
Odometer Display
The odometer displays the total distance which the vehicle has travelled. This is calculated by the instrument cluster using wheel speed signals from the ABS module.
The odometer can show 6 characters and distances up to 999,999 miles or kilometers. The total distance travelled is stored in a Electronically Erasable Programmable Read Only Memory (EEPROM) and the Random Access Memory (RAM). This ensures that the total distance is not lost if the battery is disconnected.
The odometer value is passed to other vehicle system modules on the medium speed and high speed CAN bus. This is used to record the total vehicle mileage for diagnostic purposes and when storing Diagnostic Trouble Codes (DTC).
Trip computer Information Display
The instrument cluster contains software which controls the trip computer. The computer allows the driver to access information for current fuel usage, current journey length, average speed and estimated vehicle range of fuel remaining.
The information is calculated from CAN messages from other vehicle systems, for example wheel speed signals from the ABS module and fuel injector operating data from the ECM.
A 'Trip' button is located on the end of the LH multifunction switch and allows the driver to access, in sequence, the available trip information by repeatedly pressing the button. The trip information is displayed in the following order:
- Trip distance
- The trip distance since the last reset is displayed.
- Average speed
- The average speed since the last reset is displayed.
- Average fuel consumption
- The average fuel consumption since the last reset is displayed.
- Range
- The range is displayed showing the distance which can be travelled until the fuel gage reads empty. If the range display shows dashes (-), this indicates a failure with one or both of the fuel level sensors.
The trip computer has three independent memories; A, B and Auto. Memories A and B can be set independently. The Auto memory is reset after each ignition cycle and therefore only contains information relating the current journey.
The trip information can also be accessed from the TSD located in the center console. The TSD allows the same information available with the trip button on the multifunction switch to be displayed on the TSD, with the addition of the option to reset the values in the A and B memories.
If the battery is disconnected, all trip data in memories A, B and Auto are erased.
Fuel Level Display
The fuel level display is a linear LCD display to show the usable fuel tank contents. The level display is active at all times when the ignition is on. Low fuel level is displayed as a LOW FUEL LEVEL message and an amber warning triangle in the message center.
The fuel level is obtained by fuel level sensors in the fuel tank. These are monitored by the auxiliary junction box software and their output resistance values, corresponding fuel quantity, are transmitted to the instrument cluster on the medium speed CAN bus. The instrument cluster uses the two level sensor signals to calculate the fuel tank contents. This calculation takes into account fuel movement in the tank to display a steady fuel quantity in the LCD.
The fuel level information is transmitted on the medium speed and high speed CAN bus for use by other vehicle system modules.
AUDIBLE WARNINGS
The instrument cluster can generate audible warnings to alert the driver to a displayed message and change of vehicle operating condition. The audible warning is generated by a sounder located within the instrument cluster.
The audible warnings can be generated for the warnings and are listed in order of priority, with the first being the highest priority.
- Seatbelt reminder
- EPB (High Pitch)
- ACC Driver Intervene 1
- Airbag fault
- Key in ignition switch
- ASL overspeed
- ACC Driver Intervene 2
- EPB (Low Pitch)
- Vehicle armed (entry delay)
- Gear selector not in park
- Valet mode
- Lights on reminder
- Hood operation
- Passive Entry / Passive Start (PEPS)
- Memory set
- Turn signal indicators
- Seat Belt Minder.
The audible warnings can take the form of a single chime, a number of chimes or a continuous chime. The audible warnings are initiated by a CAN message request from the requesting sub-system control module or by the instrument cluster software.