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Console: Description and Operation

OVERHEAD CONSOLE
Three overhead consoles are available on RS/RG models These are the Electronic Vehicle Information Center (EVIC), Compass Mini-Trip Computer (CMTC) or a Compass Temperature Computer (CT). All consoles are equipped with two reading/courtesy lamps and if the vehicle is equipped with a power liftgate or power sliding door(s) the overhead console will also include command switches for these features. The overhead console is mounted with one screw and two snap clips to a molded plastic retainer bracket located above the headliner.

Refer to the vehicle Owner's Manual for specific operation of each overhead console and its systems.

Compass
All the available overhead consoles on this model include Compass information. 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 three complete circles at 5 to 8 kilometers-per-hour (3 to 5 miles-per-hour), on level ground, in not less than forty-eight 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 section may be required to restore proper compass operation.

Temperature
All the available overhead consoles on this model include Temperature information. The temperature displays the outside ambient temperature 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. 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 electronic control modules (CT, CMTC, EVIC) memory. When the ignition switch is turned to the ON position again, the electronic module 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 Front Control Module (FCM). The FCM sends temperature status messages to the module over the J1850 PCI data bus circuit.

Following are general descriptions of the major components used in the overhead console. Refer to Wiring Diagrams for complete circuit schematics.