Message Center Displays

Adaptive Cruise Control

The message center provides a display showing the ACC gap setting, set speed and a graphical image of a vehicle from behind. The stop and go feature (part of the ACC) provides message displays to indicate the vehicle is stopped and to press resume to engage the cruise control again.

Brake Coach Display (HEV)

The IPC provides a brake coach display in the message center after the vehicle has come to a complete stop. It coaches the driver to brake in a manner which maximizes the amount of energy returned through the regenerative braking system. The percent displayed is an indication of the regenerative braking efficiency with 100% representing the maximun amount of energy recovery. The brake coach display can be enabled or disabled through the message center display setup menu.

Compass Display

On the IPC, the compass is displayed in the message center as a 1 or 2 character display to indicate the current direction of the vehicle (N, NE, E, SE, S, SW, W, or NW).

Digital Speedometer

NOTE: The digital speed displayed can differ slightly from the analog speedometer due to stepper motor-pointer movement, indication tolerances and gauge bias.

The IPC provides a redundant digital speedometer display in the message center. The IPC utilizes software that modifies the display to account for differences between the speedometer gauge indication and the digital display resulting from built in biasing of the indication and tolerances in speedometer stepper motor/needle movement. The digital speedometer display operates using the same vehicle speed input used to control the cruise control set speed display.

Distance Alert

The advanced driver assist display provides a distance alert as part of the ACC displays to indicate the distance to the vehicle in front and visually provide a warning when the vehicle is too close. The graphical distance display on the road becomes a solid image that increases or decreases fill based on the distance to the vehicle in front of it. As the vehicle approaches a distance requiring an alert, the display fill turns from amber to red.

DTE

The DTE is calculated in the PCM using the Running Average Fuel Economy (RAFE), which is the fuel economy up to 400 km (250 miles), and the fuel level input from the fuel sender to determine how many kilometers (miles) the vehicle can be driven based on the remaining fuel in the tank. The DTE displayed value can increase, or decrease, or stay the same value depending on customer driving patterns.

The Running Average Fuel Economy (RAFE) is not transmitted over the CAN, however the IPC will show an invalid Running Average Fuel Economy (RAFE) value in Engineering Test Mode. The DTE can vary in the short term by up to 80 km (50 miles), but is usually within 16 km (10 miles). Even if the fuel economy is relatively constant, the DTE can be off over a 80 km (50 mile) range by -24% to +38%.

The DTE display and the fuel gauge both use the fuel level input from the fuel tank and engine fuel consumption to provide their respective functions. If the fuel gauge doesn't function correctly, both the fuel gauge and the DTE display are affected.

If the DTE does not function correctly and the fuel gauge is correct, then Running Average Fuel Economy (RAFE), odometer or vehicle speed related input can be invalid.

The PCM defaults to a preset baseline L/100km (mpg) when the keep alive memory is reset or PCM is flashed and changes afterward based on driving habits and conditions.

NOTE: The customer calculated DTE can be higher or lower than the DTE displayed in the message center due to changes in driving conditions. It is important to understand how the DTE is calculated and the factors that impact the DTE display when determining how to address any DTE concerns.

Since the DTE is calculated and averaged over a longer period of time (400 km [250 miles]), varying driving conditions can have a significant impact on the current or short term DTE as opposed to the displayed DTE. This difference often leads to customer complaints of incorrect or invalid DTE. The following list provides some (not all) of the driving conditions that may lead to an incorrect or fluctuating DTE concern:

Changing between towing/not towing.
Changing driving between city and highway.
Allowing the vehicle to idle for long periods of time.
Using the remote start feature frequently to allow the vehicle to warm up, particularly when parked on a grade.
Parking or driving on grades.
Inconsistent use of gasoline or E85 fuels.
Over-fueling or not filling the tank completely (trickle filling at above full, partial filling with less than 10% of tank capacity).

The PCM uses the following network messages to control the DTE.

Fuel alcohol percent
Fuel flow volume display
Odometer count
Transport mode
Fuel level input from the IPC

Electric Vehicle (EV) Range Display (HEV)

The IPC provides a message center display indicating the estimated distance the vehicle can travel with the energy currently available. Estimates will vary based on the energy used while driving. Changes in driving patterns can cause the values to increase, decrease, or remain contant for extended periods of time.

The electric range display indicates the estimated distance the vehicle can travel on electric power only, with the engine off.

Forward Collision Warning Alert Display

When the pre-collision alert system detects that a forward collision is possible or imminent, the IPC provides a forward collision warning alert in the message center along with a chime, to alert the driver to take evasive action, or to prepare for the vehicle's auto-braking system to slow or stop the vehicle.

High Voltage Battery State of Charge Display

The high voltage battery state of charge gauge displays the total percentage of battery charge available associated with electric only driving range. A full fill display indicates the total amount of energy obtained from an external charging source (vehicle plugged in). When the fill display indicates empty, the powertrain system will automatically switch from operating in hybrid mode.

Lane Centering Assist Display

The lane centering assist system is part of adaptive cruise control. The system uses inputs from the IPMA and CCM to help keep the vehicle within the lane markings. The IPC provides message center warning messages to alert the driver to system status.

Lane Keeping System Display

The lane keeping system combines the lane keeping alert and lane keeping aid systems. The lane keeping alert system alerts the driver of unintentional drifting outside of the lane and the lane keeping aid system corrects the vehicle steering to keep the vehicle in the center of the lane. The IPC provides a lane keeping display with a view of the vehicle in the middle of a lane with right and left lane markers to indicate the vehicle position with relation to the lane markings. The lane markers change color based on the systems status with regard to vehicle intervention to keep the vehicle in the center of the lane and provides warning messages to alert the driver when they are drifting out of their lane or need to place their hands on the steering wheel

Odometer

The IPC monitors the odometer count input from the PCM and commands the odometer with a digital display in the message center.

Outside Air Temperature

The Ambient Air Temperature (AAT) sensor is hardwired to the PCM through separate input and return circuits. The PCM provides a reference voltage to the Ambient Air Temperature (AAT) sensor and monitors the change in voltage resulting from changes in resistance as determined by outside air temperature.

The PCM sends the ambient air temperature data to the HVAC module where the temperature data is filtered. The HVAC module sends the filtered outside air temperature data to the IPC to display the outside air temperature.

The HVAC module is programmed to update the messaged outside temperature data at different rates depending on several criteria to prevent false temperature displays due to a condition known as heat soaking. Heat soaking is where the outside air temperature is hotter in the location of the Ambient Air Temperature (AAT) sensor than the actual outside air temperature.

The outside air temperature display update strategy requires a starting temperature to update from. This starting temperature is controlled based on the length of time the engine is off and the engine temperature. When the engine has been off for longer than 4 hours, the update strategy begins with the unfiltered ambient air temperature input to the PCM. If the engine has been off for less than 4 hours, and the engine coolant temperature is less than 30deg. C (86deg. F), the update strategy begins with the filtered ambient air temperature equal to the unfiltered ambient air temperature. If the engine has been off for less than 4 hours, and the engine coolant temperature is greater than 30deg. C (86deg. F), the update strategy begins at the stored previous outside air temperature value.

When the sensed outside temperature rises and the vehicle speed is above 32 km/h (21 mph), the outside air temperature display updates after approximately 90 seconds. As the vehicle speed increases, the outside air temperature display updates at a faster rate that is proportional to the increase in vehicle speed. Once the vehicle speed exceeds 80 km/h (50 mph), the display updates without any delay. If the vehicle speed drops below 32 km/h (21 mph), the update delays reset. When the sensed outside temperature drops, the display updates more quickly following the drop experienced by the Ambient Air Temperature (AAT) sensor.

PRNDM/PRND

The message center provides the PRNDM/PRND display indicating which gear position the transmission is currently in, selected by the driver.

Startup/Shutdown Displays (HEV)

The IPC provides a power on - not ready to drive display in the message center when the power button is pressed without pressing the brake. For HEV, the display is blank. For PHEV, the message center displays a battery gauge along with electric range information. The display will also indicate if the vehicle is currently plugged into an external charging source, charging status, and start and end time of the charging event.

When the vehicle is shut off, the message center displays a trip summary. The trip summary shows the same information as This Trip display, and is cumulative since the last vehicle start. The trip summary information is calculated internally in the IPC. For PHEV, the message center displays charging status, and whether the vehicle is plugged into an external charging source. The charging status is provided along with either charge duration or start or end time for the current charging event.