Dakota 4WD V8-4.7L Flex Fuel (2008)
to its vehicle.
The compass unit also will compensate for vehicle magnetism acquired 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, See: Service and Repair/Procedures/Compass Demagnetizing - CMTC to restore
proper compass operation.
TEMPERATURE
NOTE: 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.
The temperature displays the outside ambient temperature in whole degrees. The temperature display can be toggled from Fahrenheit to Celsius using the
U.S./Metric push button.
Displayed temperature reading stays in the temperature unit memory. When the ignition switch is turned to the On position, the temperature will display
the memory temperature if the engine OFF time is less than 255 minutes. If the engine OFF time is more than 255 minutes, the temperature will display
the actual temperature sensed by the ambient temperature sensor. The temperature display update interval varies with the vehicle speed.
The temperature function is supported by an ambient temperature sensor. This 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 instrument cluster, also known as the Cab Compartment Node (CCN)
averages and filters the ambient temperature signal and supplies it to other modules on the CAN data bus. Data input for all other compass mini-trip
computer functions, including VFD dimming level, is received through CAN data bus messages. The maximum temperature displayed is 66°C (140° F).
It could take several miles for the accurate temperature to be displayed as the CCN filters out heat from the engine compartment.
The CMTC uses its internal programming and all of these inputs to calculate and display the requested data. If the data displayed is incorrect, perform
the self-diagnostic tests, as described in Testing and Inspection. If these tests prove inconclusive, the use of a scan tool and the proper Diagnostic
Procedures Information are recommended for further testing of the CMTC and the CAN data bus.
NOTE: The CMTC will display min and max temperatures of -40° C (-40° F) and 66°C (140° F).
