Driver/Vehicle Information Display: Description and Operation

ELECTRONIC VEHICLE INFORMATION CENTER
The Electronic Vehicle Information Center (EVIC) is located in the overhead console. The EVIC supplements the standard vehicle instrumentation.

Three versions of the EVIC module are available on the Grand Cherokee. These three versions are identical except that some models include an integral three-push button Universal Garage Door Opener (UGDO) transmitter transceiver and/or Tire Pressure Monitoring System (TPM). The three UGDO buttons are labeled with dots to indicate the channel number. All three EVIC modules feature a large Vacuum Fluorescent Display (VFD) screen for displaying information, and back-lit push buttons function switches labeled C/T (compass/temperature), RESET, STEP and MENU. The VFD screen can also display a vehicle graphic that is used for door and liftgate open indications and to show if a turn signal has been left on. The EVIC messages and displays are coordinated with warning indicators in the instrument cluster to avoid duplication.

The BCM supplies most of the information displayed by the EVIC. Display information is received over the PCI bus. The EVIC sends and receives data over the PCI bus, communicating with the BCM, PCM, and the Instrument Cluster. Tire Pressure Monitoring System information is received by the EVIC in the form of radio transmissions. The tire pressure sensors are mounted to the vehicle wheels.

The EVIC module contains a central processing unit and interfaces with other electronic modules in the vehicle over the Programmable Communications Interface (PCI) data bus network. The PCI data bus network allows the sharing of sensor information. This helps to reduce wire harness complexity reduce internal controller hardware, and reduce component sensor current loads. At the same time, this system provides increased reliability, enhanced diagnostics, and allows the addition of many new feature capabilities.

VEHICLE INFORMATION DISPLAY
The EVIC module includes the following display options:
- Compass and Temperature - provides the outside temperature and one of eight compass readings to indicate the direction the vehicle is facing.
- Average fuel economy - shows the average fuel economy since the last trip computer reset.
- Distance to empty - shows the estimated distance that can be travelled with the fuel remaining in the fuel tank. This estimated distance is computed using the average miles-per-gallon from the last 30 gallons of fuel used.
- Instant fuel economy - shows the present fuel economy based upon the current vehicle distance and fuel used information.
- Trip distance - shows the distance travelled since the last trip computer reset.
- Elapsed time - shows the accumulated ignition-on time since the last trip computer reset.
- Distance to service - shows the distance remaining until the next scheduled service interval.
- Tire Pressure - shows the tire pressure in each tire.
- Blank screen - the EVIC compass/temperature/ trip computer VFD is turned OFF.

The EVIC is capable of displaying the following driver alert messages, which are accompanied by an audible announcement consisting of a series of beeps:
- TURN SIGNALS ON (with vehicle graphic) - Indicates that a turn signal has remained on for about 1.6 kilometers (one mile).
- PERFORM SERVICE - Indicates that a customer programmable service interval distance has been reached.
- DOOR OPEN (one or more, with vehicle graphic) - Indicates that a door is open or not fully closed.
- LIFTGATE OPEN (with vehicle graphic) - Indicates that the liftgate is open or not fully closed.
- LIFTGLASS OPEN (with vehicle graphic) - Indicates that the liftglass is open or not fully closed.
- COOLANT LEVEL LOW (with vehicle graphic) - Indicates that the coolant level in the engine coolant reservoir is low.
- XX LOW PRESSURE (with vehicle graphic) - Indicates that the air pressure in the selected tire is low.
- WASHER FLUID LOW (with vehicle graphic) - Indicates that the fluid level in the washer fluid reservoir is low.

The EVIC will not display information for any of the screens for which it did not receive the proper PCI bus data. Refer to the symptom list in the Overhead Console section for problems related to the EVIC.

The EVIC "Menu" push button provides the vehicle operator with a user interface, which allows the selection of several optional customer programmable electronic features to suit individual preferences. Refer to ELECTRONIC VEHICLE INFORMATION CENTER PROGRAMMING in the Service Procedures section of this group for more information on the customer programmable feature options.

If the vehicle is equipped with the optional memory system, the EVIC will display the following memory system messages:
- MEMORY # X POSITION SET (X = Driver 1 or Driver 2) - This message appears in the EVIC display each time the memory system is successfully programmed. It is accompanied by an audible announcement chime tone.
- MEMORY SYSTEM DISABLED - The memory system is automatically disabled while the driver side seat belt is fastened and/or while the automatic transmission gear selector is in any position except Park or Neutral. This message appears in the EVIC display as a reminder when a memory switch push button is depressed while the memory system is disabled. If the REMOTE LINKED TO MEMORY customer programmable feature has been selected, this message will also appear when the Unlock button of the Remote Keyless Entry (RKE) transmitter is depressed while the memory system is disabled.

If the vehicle is equipped with the optional Universal Transmitter transceiver, the EVIC will also display messages and an icon indicating when the Universal Transmitter is being trained, which of the three transmitter buttons is transmitting, and when the transceiver is cleared.

If the vehicle is equipped with the optional Tire Pressure Monitoring System, the EVIC will also display messages and an icon indicating when the tire air pressure falls below a given set-point, and which of the five tires is transmitting the low pressure warning, and when the condition is cleared. Refer to the Tires/Wheels section for complete Tire Pressure Monitoring System description. Refer to this section for EVIC modules function description for the Tire Pressure Monitoring.

Data input for all EVIC functions, including VFD dimming level, is received through PCI data bus messages. The EVIC module uses its internal programming and all of its data inputs to calculate and display the requested data. If the data displayed is incorrect, perform the self-diagnostic tests as described in this group. If these tests prove inconclusive, the use of a DRB III scan tool and the proper Diagnostic Procedures are recommended for further testing of the EVIC module and the PCI data bus.

The EVIC module cannot be repaired, and is available for service only as a unit. This unit includes the push button switches and the plastic housed module. If any of these components are faulty or damaged, the complete EVIC module must be replaced. The incandescent bulbs used for EVIC push button back-lighting and the display lens are available for service replacement.

The EVIC has access to both non-switched and ignition switched sources of battery current so that some of its features remain operational at any time, while others may only operate with the ignition switch in the ON position. When the ignition switch is turned to the ON position, the EVIC module VFD will return to the last function being displayed before the ignition was turned to the OFF position.

The compass/temperature display is the normal EVIC display With the ignition switch in the ON position, momentarily depressing and releasing the CIT (compass/temperature) push button switch will cause the EVIC to return to the compass/temperature/trip computer display mode from any other mode. While in the compass/temperature/trip computer display mode, momentarily depressing and releasing the Step push button will step through the available trip computer display options.

The EVIC trip computer features several functions that can be reset. The functions that can be reset are: average fuel economy trip odometer and elapsed time. With the ignition switch in the ON position and with one of the functions of the trip computer that can be reset currently displayed, depressing the Reset push button twice within three seconds will perform a global reset, and all of the trip computer information that can be reset will be reset to zero. With the ignition switch in the ON position and the function that is to be reset currently displayed, momentarily depressing and releasing the Reset push button once will perform a local reset, and only the value of the displayed function will be reset to zero. A global or local reset will only occur if the function currently displayed is a function that can be reset. The distance to service function can also be reset using the local reset method, but it will reset back to the Service Interval distance that is set in the EVIC programmable features mode. Refer to ELECTRONIC VEHICLE INFORMATION CENTER PROGRAMMING in the Service Procedures section of this group for more information on setting the Service Interval.

The EVIC receives the following messages from the Body Control Module (BCM):
- Verification of US/Metric status
- VF display dimming brightness and exterior lamp status
- Trip Odometer data
- Elapsed Ignition On Time data
- Fuel Economy (Average and Instantaneous)
- Distance to Empty
- Outside Temperature
- Distance to service
- Driver warning messages

The EVIC transmits the following messages to the BCM:
- Status Request: Beep, Reset, US/M Toggle
- Current Display

The EVIC receives the following message from the PCM:
- Vehicle Speed

Step Button
The STEP Button can be used in one of the following three ways:

1. To sequentially select one of seven displays or blank display in the following order:
- Average Fuel Economy
- Distance to Empty
- Instantaneous Fuel Economy
- Trip Odometer
- Time Elapsed
- Distance to Service Message
- Individual Tire Pressure
- Off (Blank)

2. To set the magnetic variance zone when VARIANCE = X (X = 1 - 15) is indicated in the VF Display.
3. To select the displayed programmable feature setting.

Menu Button
Use the MENU button to sequentially step the EVIC through the programmable features.
Use the MENU button to enter the Tire Pressure Monitoring (TPM) Training Procedure.

Reset Button
The RESET Button has two different functions:
1. To clear the trip functions that may be reset
2. To enter and exit the diagnostic mode

Pressing the RESET button once will clear the trip function that is currently being displayed (except Distance to Service) and the EVIC will send a PCI bus beep request to the BCM. If the RESET button is pressed again within 3 seconds, the EVIC will reset ALL of the trip functions and an additional beep request is sent to the BCM. The trip functions that may be reset are:
- Average Fuel Economy
- Trip Odometer
- Elapsed Time

A reset will only occur if one of the trip functions that may be reset is currently being displayed.

Pressing the RESET button for more than three (3) seconds resets the Distance to Service function while the Distance to Service message is being displayed. The EVIC module will send a beep request to the BCM.

Simultaneously pressing the RESET button and the C/T button while turning the ignition from OFF to ON will enter the EVIC into the self-diagnostic mode.

Compass/Temperature (C/T) Button
Actuating the Compass/Temperature Button (C/T) will cause the EVIC to display the compass and temperature information. This function will operate from another traveler display or from the programmable feature mode.

Traveler Display Functions
Using the STEP button will change the EVIC between modes of operation and display the appropriate information according to data received from the PCI Bus.




Setting Magnetic Zone Variance
Variance is the difference between magnetic North and geographic North. For proper compass function, the correct variance zone must be set. Refer to the Zone Variance map for the correct zone. Follow these steps to check or change the variance zone:
- The ignition switch must be in the ON position and the EVIC display must not be blank.
- If the compass/temperature data is not currently being displayed, momentarily press and release the C/T button to display compass/temp information.
- Press and hold the RESET button until VARIANCE = XX is displayed. The EVIC will display the variance zone stored in memory and the word VARIANCE.
- Use the STEP button to select the proper variance zone number, 1 through 15.
- After selecting the proper zone number, momentarily press and release the RESET button. The variance zone is then stored in the memory and the EVIC returns to normal operation.

Ambient Temperature Sensor
The ambient air temperature is monitored by the BCM and displayed by the EVIC. The BCM receives a hardwire input from the Ambient Temperature Sensor (ATS).

The ATS is a variable resistor that operates on a 5-volt reference signal circuit hardwired from the BCM. The resistance in the ATS changes as the outside temperature rises or falls. The BCM senses the change in reference voltage through the ATS resistor. Based on the resistance of the ATS, the BCM is programmed to correspond to a specific temperature. The BCM stores and filters the ambient temperature data and transmits this data to the EVIC via the PCI Bus. The ATS cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.

Ambient Temperature Sensor Fault Codes
The outside temperature function is supported by the ambient temperature sensor (ATS), a signal and ground circuit hardwired to the BCM, and the EVIC display.

If the EVIC display indicates 54 °C (130 °F) or the ATS sense circuit is shorted to ground, the temp display will be 54 °C (130 °F) to indicate a SHORT circuit condition.

If the EVIC display indicates -40 °C (-40 °F) or the ATS sense circuit is open, the temp display will be -40 °C (-40 °F) to indicate an OPEN circuit condition.

If there is an OPEN or SHORT circuit condition, it must be repaired before the EVIC VFD can be tested.

The ATS is supported by the BCM. Ambient Temperature Sensor DTCs will be recorded in the BCM. The ATS can be diagnosed using the following Sensor Test. Test the ATS circuits using the diagnostics in the Body Diagnostic Procedures Manual. If the EVIC passes the self test, and the ATS, the circuits, and PCI bus communications are confirmed to be OK, but the EVIC temperature display is inoperative or incorrect, replace the BCM.

HOMELINK Universal Transmitter
If equipped, the HomeLink Universal Transmitter is integrated into the overhead console. For added security it will operate home security systems that use coded signals known generically as Rolling Codes. The overhead console display provides visual feedback to the driver, indicating which HomeLink transmitter channel button is being pressed. The HomeLink can learn and store up to three separate transmitter radio frequency codes to operate garage door openers, security gates, and security lighting. The HomeLink buttons are marked with one, two, or three dots. For complete information, refer to Universal Transmitter in the Owner's Manual.

Electronic Vehicle Information Center Chime
The Electronic Vehicle Information Center (EVIC) uses the chime warning system for two different kinds of support. In addition to requesting chime tones from the Body Control Module (BCM) as tactile beep support, the EVIC is programmed to send chime request messages over the Programmable Communications Interface (PCI) data bus when it detects the following conditions:
- Door Open Warning - A door is open above a critical speed [about 16 km/h (10 mph) for the driver side front door, or about 5 km/h (3 mph) for any other door].
- Liftgate Open Warning - The liftgate is open above a critical speed [about 5 km/h (3 mph)].
- Liftglass Open Warning - The liftgate flip-up glass is open above a critical speed [about 5 km/h (3 mph)].
- Low Coolant Level Warning - The coolant level in the engine coolant reservoir is low.
- Perform Service Alert - An audible alert that a "Perform Service" reminder message is being displayed by the EVIC.
- Turn Signal ON Warning - A turn signal remains on for about 1.6 kilometers (one mile).
- Washer Fluid Low Warning - The fluid level in the washer reservoir is low.

See the owner's manual in the vehicle glove box for more information on the features, use and operation of the EVIC. (Refer to ELECTRICAL/OVERHEAD CONSOLE/ELECTRONIC VEHICLE INFO CENTER - DESCRIPTION) for more information on the EVIC.

Compass
While in the compass/temperature mode, the compass will display the direction in which the vehicle is pointed using the eight major compass headings (Examples: north is N, northeast is NE). The self-calibrating compass unit requires no adjusting in normal use. The only calibration that may prove necessary is to drive the vehicle in one circle at 5 to 8 km/h (3 to 5 mph), on level ground, in not less than 20 seconds. This will reorient the compass unit to its vehicle.

The compass unit also will compensate for magnetism the body of the vehicle may acquire during normal use. However, avoid placing anything magnetic directly on the roof of the vehicle. Magnetic mounts for an antenna, a repair order hat, or a funeral procession flag can exceed the compensating ability of the compass unit if placed on the roof panel. Magnetic bit drivers used on the fasteners that hold the overhead console assembly to the roof header can also affect compass operation. If the vehicle roof should become magnetized, the demagnetizing and calibration procedures found in this group may be required to restore proper compass operation.

Temperature
The outside ambient temperature is displayed in whole degrees. The temperature display can be toggled from Fahrenheit to Celsius by selecting the desired U.S./Metric option from the customer programmable features as described in ELECTRONIC VEHICLE INFORMATION CENTER PROGRAMMING in the Standard Procedures section of this group. The displayed temperature is not an instant reading of conditions, but an average temperature. It may take the temperature display several minutes to respond to a major temperature change, such as driving out of a heated garage into winter temperatures.

When the ignition switch is turned to the OFF position, the last displayed temperature reading stays in the Body Control Module (BCM) unit memory. When the ignition switch is turned to the ON position again, the EVIC will display the memory temperature for one minute; then update the display to the current average temperature reading within five minutes.

The temperature function is supported by an ambient temperature sensor. The sensor is mounted outside the passenger compartment near the front and center of the vehicle, and is hard wired to the Body Control Module (BCM). The BCM sends temperature status messages to the EVIC module over the PCI data bus network. The ambient temperature sensor is available as a separate service item.

UNIVERSAL TRANSMITTER
The Grand Cherokee Limited model has a Universal Garage Door Opener (UGDO) transceiver as standard factory-installed equipment. The UGDO is optional on Laredo models. The UGDO transceiver is integral to the Electronic Vehicle Information Center (EVIC), which is located in the overhead console. The only visible component of the UGDO are the three transmitter push buttons centered between the four EVIC push buttons located just rearward of the EVIC display screen in the overhead console. The three UGDO transmitter push buttons are identified with one, two or three dots so that they be easily identified by sight.

Each of the three UGDO transmitter push buttons controls an independent radio transmitter channel. Each of these three channels can be trained to transmit a different radio frequency signal for the remote operation of garage door openers, motorized gate openers, home or office lighting, security systems or just about any other device that can be equipped with a radio receiver in the 288 to 410 Megahertz (MHz) frequency range for remote operation. The UGDO is capable of operating systems using either rolling code or non-rolling code technology

The EVIC module displays messages and a small house-shaped icon with one, two or three dots corresponding to the three transmitter buttons to indicate the status of the UGDO. The EVIC messages are:
- Cleared Channels - Indicates that all of the transmitter codes stored in the UGDO have been successfully cleared.
- Training - Indicates that the UGDO is in its transmitter learning mode.
- Trained - Indicates that the UGDO has successfully acquired a new transmitter code.
- Transmit - Indicates that a trained UGDO transmitter button has been depressed and that the UGDO is transmitting.

The UGDO cannot be repaired, and is available for service only as a unit with the EVIC module. This unit includes the push button switches and the plastic module. If any of these components are faulty or damaged, the complete EVIC module must be replaced.

The universal transmitter operates on a non-switched source of battery current so the unit will remain functional, regardless of the ignition switch position. For more information on the features, programming procedures and operation of the universal transmitter, see the owner's manual in the vehicle glove box.

AMBIENT TEMPERATURE SENSOR
Ambient air temperature is monitored by the Electronic Vehicle Information Center (EVIC) through ambient temperature messages received from the Body Control Module (BCM) over the Programmable Communications Interface (PCI) data bus network. The BCM receives a hard wired input from the ambient temperature sensor. The ambient temperature sensor is a variable resistor mounted to a bracket that is secured with a screw to the right side of the headlamp mounting module grille opening, behind the radiator grille and in front of the engine compartment.

Refer to Body Control Module in Electronic Control Modules. For complete circuit diagrams, refer to the appropriate wiring information. The ambient temperature sensor cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.

The ambient temperature sensor is a variable resistor that operates on a five-volt reference signal sent to it by the BCM. The resistance in the sensor changes as temperature changes, changing the temperature sensor signal circuit voltage to the BCM. Based upon the resistance in the sensor, the BCM senses a specific voltage on the temperature sensor signal circuit, which it is programmed to correspond to a specific temperature. The BCM then sends the proper ambient temperature messages to the EVIC over the PCI data bus.

The temperature function is supported by the ambient temperature sensor, a wiring circuit, the Body Control Module (BCM), the Programmable Communications Interface (PCI) data bus, and a portion of the Electronic Vehicle Information Center (EVIC) module. If any portion of the ambient temperature sensor circuit fails, the BCM will self-diagnose the circuit. A temperature reading of 130 °F will appear in the EVIC display in place of the temperature when the sensor circuit is shorted. A temperature reading of -40 °F will appear in the EVIC display in place of the temperature when the sensor circuit is open.

The ambient temperature sensor circuit can also be diagnosed by referring to Diagnosis and Testing - Ambient Temperature Sensor, and Diagnosis and Testing - Ambient Temperature Sensor Circuit. If the temperature sensor and circuit are confirmed to be OK, but the temperature display is inoperative or incorrect, refer to Diagnosis and Testing - Electronic Vehicle Information Center in this group. For complete circuit diagrams, refer to the appropriate wiring information.