Overhead Console
OVERHEAD CONSOLECOMPASS/TEMPERATURE MODULE, COMPASS/MINI-TRIP COMPUTER or ELECTRONIC VEHICLE INFORMATION CENTER
The Compass/Temperature Module (CT), Compass/Mini-Trip Computer (CMTC) or Electronic Vehicle Information Center (EVIC) is located in the overhead console. The CT provides the vehicle operator with only outdoor temperature and the compass heading. The CMTC or EVIC supplements the standard vehicle instrumentation. The CMTC and EVIC use a vacuum fluorescent (VF) display to supply the vehicle operator with a compass heading, outdoor temperature, average fuel economy, distance to empty, instantaneous fuel economy, trip odometer, elapsed ignition on time, distance to service, warning messages, and service messages.
The difference between a CMTC and an EVIC is that only the EVIC provides additional memory, feature programming, and warning messages. The EVIC is capable of displaying warning messages and memory system messages when the vehicle is equipped with memory systems. The EVIC also provides the interface to enable and disable vehicle programmable features when the vehicle is equipped with certain features.
If equipped, the EVIC is also available with an integrated Universal Garage Door Opener (UGDO) known as HomeLink(R). Also if equipped, the EVIC is available with a Tire Pressure Monitoring (TPM) System. The EVIC may also be equipped with up to 4 power door switches: ON/OFF, Left Sliding Door, Right Sliding Door, and Liftgate.
The CT function buttons are labeled C/T and US/M. The CMTC function buttons are labeled USIM, C/T, RESET, and STEP. The EVIC function buttons are labeled C/T, RESET STEP and MENU. The three UGDO buttons are labeled with dots to indicate the channel number.
The BCM supplies most of the information displayed by the CMTC/EVIC. Display information, except for the internal compass function, is received over the PCI bus. The FCM supplies the ambient temperature sensor information via the PCI bus. The CMTC/EVIC sends and receives data over the PCI bus, communicating with the BCM, PCM, FCM, 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. For complete information, refer to the Tire Pressure Monitoring system section in this publication.
VEHICLE INFORMATION DISPLAY
The CMTC/EVIC provides the following functions:
- Compass direction
- Outside temperature
- Elapsed ignition on time
- Distance to empty
- Average fuel economy
- Instantaneous fuel economy
- Trip odometer
- Distance to service
The EVIC will also display the following driver alert messages:
- TURN SIGNAL ON (with vehicle graphic)
- PERFORM SERVICE
- DOOR OPEN (individual or multiple doors, with graphic)
- LOW or HIGH TIRE(S) PRESSURE (when equipped)
- ADJUSTABLE PEDAL DISABLED CRUISE ENGAGED (when equipped)
- ADJUSTABLE PEDAL DISABLED VEHICLE IN REVERSE (when equipped)
An audible chime or chimes will accompany any displayed warning messages. Chime requests with an OPEN message are dependent upon vehicle speed.
The CT/CMTC/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 CT/CMTC/EVIC.
The CMTC/EVIC receives the following messages from the Body Control Module (BCM):
- Verification of US/Metric status
- VF display dimming brightness and exterior lamp status
- Elapsed Ignition On Time data
- Fuel Economy (Average and Instantaneous)
- Distance to Empty
- Distance to service
- Driver warning messages
The CT/CMTC/EVIC receives the following messages from the Front Control Module (FCM):
- Outside Temperature
The CMTC/EVIC receives the following messages from the Powertrain Control Module (PCM):
- Trip Odometer data
- Vehicle Speed
The EVIC receives the following messages from the Adjustable Pedal System Module (APS):
- APS status warnings
The CMTC/EVIC transmits the following messages to the BCM:
- Status Request: Beep, Reset, US/M Toggle
- Current Display
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
- 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. (when equipped.)
MENU BUTTON (EVIC Only)
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 CMTC/EVIC will send a PCI bus beep request to the BCM. If the RESET button is pressed again within 3 seconds, the CMTC/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 CMTC/EVIC module will send a beep request to the BCM.
Simultaneously pressing the RESET button and the STEP button while turning the ignition from Off to On will enter the CMTC/EVIC into the self-diagnostic mode.
COMPASS/TEMPERATURE (C/T) BUTTON
Actuating the Compass/Temperature Button (C/T) will cause the CMTC/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 CMTC/ EVIC between modes of operation and display the appropriate information according to data received from the PCI Bus.
COMPASS/TEMPERATURE
The CMTC/EVIC simultaneously displays the compass reading and the outside temperature. Outside temperature information is received via the PCI bus from the FCM.
The CMTC/EVIC module internally senses and calculates the compass direction.
COMPASS OPERATION - ALL
Upon ignition on, if the calibration information stored in the CMTC memory is within the normal range, the CMTC will perform in slow Auto-Cal mode. In slow Auto-Cal mode, the CMTC continuously compensates for the slowly changing magnetic field of the vehicle. The compass module detects changes in the vehicle magnetism and makes appropriate internal corrections to ensure proper displayed direction.
However, if the calibration information stored in the CMTC memory is not within the normal range at ignition on, the CMTC will enter fast Auto-Cal. CAL is displayed along with the temperature.
Auto activation of the fast Auto-Cal mode will also occur when the CMTC is subjected to high magnetic field strength levels, which cause all compass readings to be erroneous for a continuous period of five (5) minutes. During fast Auto-Cal, CAL will be displayed along with the temperature.
Fast Auto-Cal can also be performed manually, by pressing and holding the RESET button for 10 seconds during the Compass/Temperature display mode.
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:
CMTC/EVIC
- The ignition switch must be in the On position and the CMTC/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 (approximately 5 seconds) until VARIANCE = XX is displayed.
The CMTC/EVIC Will display the variance zone stored in memory and the word VARIANCE.
- Use the RESET 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 CMTC/EVIC returns to normal operation.
CT
- The ignition switch must be in the On position and the C/T display must not be blank.
- Press and hold the C/T and US/M buttons (approximately 5 seconds) until VARIANCE = XX is displayed. The C/T will display the variance zone stored in memory and the word VARIANCE.
- Use the US/M button to select the proper variance zone number, 1 through 15.
- After selecting the proper zone number, momentarily press and release the C/T button. The variance zone is then stored in the memory and the C/T returns to normal operation.
COMPASS CALIBRATION
The compass module has 2 types of auto-calibration; slow-cal and fast-cal. Slow-cal ensures that during normal vehicle operation the compass performs auto-calibration functions to keep the compass sensors in their proper operating range. Whenever the ignition is On and the CT/CMTC/EVIC receives PCI bus data indicating that engine RPM is greater than zero, auto-calibration is performed continuously.
If the calibration information stored in the compass module memory is not within the normal range after a power-up cycle, the compass will display CAL. The CT/CMTC/EVIC will enter into the fast-cal mode until calibration is complete.
To enter the compass into Manual Calibration mode, perform the following steps:
- Drive the vehicle to an area away from any large metal objects or overhead power lines.
- Ensure that the proper variance zone is selected. See "Setting Magnetic Zone Variance."
- The ignition switch must be in the On position and the CMTC/EVIC display must not be blank.
- Press the C/T button to view the Compass/Temperature display.
- Press and hold the RESET button (approximately 10 seconds) until CAL is displayed, then release the button.
- Drive slowly, less than 5 mph (8 kph) in at least 1 complete 360-degree circle.
- CAL will remain illuminated to alert the driver that the compass is in the calibration mode.
- After calibration is complete, CAL will turn off.
NOTE: For C/T Manual Calibration, perform the same procedure as above, but press and hold the C/T and US/M buttons until CAL is displayed.
If the compass appears blank, unable to be calibrated, or the compass displays false indications, the vehicle must be demagnetized. Refer to Compass Demagnetizing Procedure in the Service Manual.
SELF-CHECK DIAGNOSTICS
The CT/CMTC/EVIC is capable of performing a diagnostic self check on its internal functions. Diagnostics may be performed using a DRBIII(R) or by using the following procedure.
To enter the Self-Check mode:
1. For CMTC/EVIC: With the ignition switch in the OFF position, depress and hold the RESET and the STEP buttons.
For CT: With the ignition switch in the OFF position, depress and hold the C/T and the USIM buttons.
2. Turn the ignition switch to the ON position.
3. Continue to hold both buttons until the software versions are displayed, then release the buttons.
4. All of the VFD segments will illuminate for 2 - 4 seconds. Check for segments that do not illuminate or illuminate all the time.
5. When the self-check is complete the EVIC will display one of the following messages:
- PASS SELF TEST
- FAILED SELF TEST
- NOT RECEIVING J1850 MESSAGE
When the self-check is complete the CT/CMTC will display one of the following messages:
- PASS
- FAIL
- BUS
To exit the Self-Check mode:
1. For the CMTC/EVIC: Depress the STEP or RESET button, or cycle the ignition switch and the CMTC/EVIC will return to normal operation.
For the C/T: Depress the C/T or US/M button, or cycle the ignition switch and the CT will return to normal operation.
If a Communication fault is displayed, refer to the symptom list. If a FAIL or FAILED is displayed, the CT/CMTC/EVIC must be replaced.
AMBIENT TEMPERATURE SENSOR
The ambient air temperature is monitored by the FCM and displayed by the CT/CMTC/EVIC. The FCM 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 FCM. The resistance in the ATS changes as the outside temperature rises or falls. The FCM senses the change in reference voltage through the ATS resistor. Based on the resistance of the ATS, the FCM is programmed to correspond to a specific temperature. The FCM stores and filters the ambient temperature data and transmits this data to the CMTC/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 FCM, and the CMTC/EVIC display.
If the CMTC/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 CMTC/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 CMTC/EVIC VFD can be tested.
The ATS is supported by the FCM. Ambient Temperature Sensor DTCs will be recorded in the FCM. The ATS can be diagnosed using the following Sensor Test. Test the ATS circuits using the diagnostics in the Body Diagnostic Procedures. If the CMTC/EVIC passes the self-test, and the ATS, the circuits, and PCI bus communications are confirmed to be OK, but the CMTC/EVIC temperature display is inoperative or incorrect, replace the FCM.
AMBIENT TEMPERATURE SENSOR TEST
1. Turn the ignition OFF.
2. Disconnect the ATS harness connector.
3. Measure the resistance of the ATS using the following min/max values:
Temperature Sensor Resistance
0°C (32°F) 29.33 - 35.99 Kilohms
10°C (m50°F) 17.99 - 21.81 Kilohms
20°C (m68 °F) 11.37 - 13.61 Kilohms
25°C (77 °F) 9.12 - 10.86 Kilohms
30°C (86 °F) 7.37 - 8.75 Kilohms
40°C (104 °F) 4.90 - 5.75 Kilohms
The sensor resistance should read between these mill/max values. If the resistance values are not OK, replace the Sensor.
HOMELINK(R) UNIVERSAL TRANSMITTER
If equipped, the HomeLink(R) 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(R) transmitter channel button is being pressed. The HomeLink(R) can learn and store up to three separate transmitter radio frequency codes to operate garage door openers, security gates, and security lighting. The HomeLink(R) buttons are marked with one, two, or three dots. For complete information, refer to Universal Transmitter in the Service Manual or the Owner's Manual.
TIRE PRESSURE MONITORING SYSTEM (TPM)
If equipped with the Tire Pressure Monitoring System (TPM), each of the vehicles four wheels will have a valve stem with a pressure sensor and radio transmitter built in. Signals from the tire pressure Sensor/Transmitters are received and interpreted by the Electronic Vehicle Information Center (EVIC).
A Sensor/Transmitter in a mounted wheel will broadcast its detected pressure once per minute when the vehicle is moving faster than 32 km/h (20 mph). Each Sensor/Transmitter's broadcast is uniquely coded so that the EVIC can determine the location.
TRAINING THE EVIC
The EVIC can be trained to recognize the source locations of the Sensor/Transmitter signals. The training procedure is given below:
1. From the Programmable Features List select "RETRAIN TIRE SENSORS Y/N" using the EVIC MENU button.
Use the STEP button to select and the MENU button to confirm "YES". The EVIC will initiate the following procedure:
2. A display will prompt the user to: "TRAIN DRIVER FRONT SENSOR". At this point the user must set the left front tire Sensor/Transmitter to learn mode by positioning a magnet (Relearn Magnet special tool 8821) over the valve stem for at least 5 seconds. The Sensor / Transmitter in the front left tire will transmit a message indicating to the EVIC that it is in learn mode. When the EVIC has received this message and is assured that it has learned an ID, the EVIC will request a horn chirp via a bus message and then display the next train request.
NOTE: The EVIC will allow 60 seconds from the first train request display to the receipt of a unique learn ID message from the first Sensor / Transmitter and 30 seconds for each succeeding wheel. If either of these timers expires, the EVIC will abort the training procedure and revert to previous settings. The EVIC will not store one ID for multiple locations.
3. The EVIC will request the initiation of a training sequence for each tire, one-by-one in a clockwise direction around the vehicle (Left Front, Right Front, Right Rear, and Left Rear).
NOTE:
1. If one or all Sensor/Transmitters cannot be trained, move vehicle to avoid radio frequency interference.
2. If one Sensor/Transmitter still cannot be trained, replace it and retry.
3. If all Sensor/Transmitters still fail to train, replace the EVIC.
4. Once all tires are successfully learned, the previous set of stored IDs will be replaced by the new IDs, and the EVIC will display, "TRAINING COMPLETE" until a button is pressed.
If the vehicle is equipped with the HomeLink(R) feature and a HomeLink(R) button is pressed at any time during the training procedure, the EVIC module will immediately exit the training procedure, discard any IDs learned in the current session and perform the HomeLink(R) function. After the button is released, the module will display "RETRAIN TIRE SENSORS? NO".
The training procedure can be stopped at any time by pressing the C/T, STEP RESET; or MENU button. When any of these buttons are pressed the EVIC will display "TRAINING ABORTED" until another button is pressed and then display "RE-TRAIN TIRE SENSORS? NO". Sensor/transmitter replacement or tire rotation will require retraining of the EVIC.
PRESSURE THRESHOLDS
The EVIC will monitor the tire pressure signals from the tire Sensor/Transmitters and determine if any tire has gone below the low pressure threshold or exceeded the high pressure threshold. Refer to the table.
CRITICAL AND NON-CRITICAL SYSTEM ALERTS
Critical:
A critical alert will be triggered when a tire pressure has gone below or above a set threshold pressure. The EVIC will request a chime and then display "X TIRE(S) LOW PRESSURE" or TIRE(S) HIGH PRESSURE". "X" will be the number of tires reporting low or high pressure. The message will display for the duration of the current ignition cycle or until an EVIC button is pressed. If the display is removed without correcting the condition, it will reappear without a chime after 300 seconds to warn the driver of the low or high-pressure condition.
Non-Critical:
A non-critical alert with no chime will be triggered when no signal is received from a Sensor / Transmitter or when a Sensor/Transmitter low battery condition is detected. The EVIC will display "SERVICE TIRE PRESS. SYSTEM".
SYSTEM FAULTS
There are two conditions that will cause a Tire Pressure Monitoring System fault to be set. All fault codes are associated with a specific wheel location.
1. If the EVIC detects a non-transmitting Sensor/Transmitter condition, it will:
a. Store an active fault code.
b. Request a chime
c. Display "SERVICE TIRE PRESS. SYSTEM".
1. When the EVIC receives a Low Sensor/ Transmitter battery report from a Sensor / Transmitter, it will:
a. Store an active fault code.
b. Request a chime.
c. Display "SERVICE TIRE PRESS. SYSTEM".
Use the DRBIII(R) Inputs/Outputs function to further isolate the specific concern. The DRBIII(R) can be queried to determine the status and battery condition for each Sensor/Transmitter.
SPARE WHEEL AUTO-DETECT
If the spare tire is mounted on the vehicle, the EVIC will:
1. Detect the change after 15 minutes at or above 32 km/h (20 mph)
2. Query driver: "SPARE TIRE IN USE?" Use the MENU button for YES, and the STEP button for NO. For S, the EVIC will revert to the previous display and wait five hours. After five hours the EVIC will proceed as in the NO response below.
3. For a NO response, after 15 minutes, the EVIC will display: "ALL 5 TIRES W/VEHICLE? Y" Use the STEP button to select YES or NO, and the MEN button to confirm.
For a "YES" response, the EVIC will display "SERVICE TIRE PRESS. SYSTEM".
For a "NO" response, the EVIC will revert to previous display and display "ALL 5 TIRES W/VEHICLE ? Y" every time the ignition is cycled to RUN and the missing tire ID is not received.
DIAGNOSING AND CLEARING SYSTEM FAULTS
All Tire Pressure Monitoring System Faults are specific to one location. If a no-transmit, "LOW BATTERY", "LOW or HIGH PRESSURE" fault is detected, the location can be determined by the DRBIII(R). The appropriate Sensor/Transmitter can then be replaced or the out-of-specification pressure condition can be corrected.
- If a single Sensor/Transmitter cannot be detected by the EVIC, replace that Sensor/Transmitter.
- If none of the Sensor/Transmitters can be detected, refer to symptoms in the Tire Pressure Monitor section.
- If a BUCKET COUNTER test fails, and one or more Sensor/Transmitters does not transmit, replace the affected Sensor/Transmitter.
- If none of the Sensor/Transmitter causes the BUCKET COUNTER to advance, replace the EVIC.
- If the EVIC displays SERVICE TIRE PRESS. SYSTEM and the DRBIII(R) sees no Sensor/Transmitter fault or pressure out of specification;
1. Attempt the Retrain procedure. If the display reoccurs,
2. Replace the EVIC.
SYSTEM TEST
A test of the Tire Pressure Monitoring System can be initiated in the EVIC. The test sequence is as follows:
1. Perform the RETRAIN TIRE SENSORS procedure.
2. Press and hold the RESET and STEP buttons for five seconds.
3. The EVIC will display BUCKET COUNTERS.
4. Drive the vehicle at 32 km/h (20 mph) for at least 2 minutes.
5. The counters will increase by one each time a Sensor/Transmitter signal is received by the EVIC.
6. Observe that the COUNTERS register at least 3 receptions for each Sensor/Transmitter.
7. Replace any Sensor/Transmitter that does not meet this specification.
The test will continue until any EVIC button is pressed or until the ignition is cycled to OFF.