Vacuum-Fluorescent Displays
The Vacuum-Fluorescent Display (VFD) (25) (34) units are soldered to the CCN electronic circuit board. Both the standard one located below the tachometer and the optional Compass Mini-Trip Computer (CMTC) display located below the speedometer are fixed segment displays.
The odometer and trip odometer information are stored in the instrument cluster memory. This information can be increased when the proper inputs are provided to the instrument cluster, but the information cannot be decreased. The odometer can display values up to 999, 999 kilometers (999, 999 miles). The odometer latches at these values, and will not roll over to zero. The trip odometer can display values up to 999.9 kilometers (999.9 miles) before it rolls over to zero.
The odometer display does not show leading zeroes, does not have a decimal point and will not show values less than a full unit (kilometer or mile). The unit of measure (km or miles ) for the odometer display is not shown in the VFD. The unit of measure for the instrument cluster odometer/trip odometer is selected at the time that it is manufactured, and cannot be changed.
The illumination intensity of the VFD units is controlled by the CCN circuitry based upon electronic dimming level messages received over the Controller Area Network (CAN) data bus indicating the exterior lighting is turned ON and the dimming level selected using the panel dimmer function of the control sleeve on the control stalk of the left (lighting) multi-function switch. The illumination intensity of the CCN VFD units is synchronized with that of other display units in the vehicle by sending the same electronic dimming level message inputs to all electronic modules in the vehicle over the CAN or Local Interface Network (LIN) data bus. However, on domestic market vehicles only, if the Tire Pressure Monitor (TPM) indicator or Malfunction Indicator Lamp (MIL) is active, the odometer VFD will illuminate at full daytime brightness until both the TPM indicator and the MIL are extinguished.
During daylight hours (exterior lamps are OFF) the odometer VFD is illuminated at full brightness for clear visibility. At night (exterior lamps are ON), the VFD lighting level is adjusted with the other cluster general illumination lamps using the panel lamps dimmer function of the interior lighting control sleeve on the left multi-function switch control stalk. However, a PARADE mode position of the control sleeve allows the VFD to be illuminated at full brightness if the exterior lamps are turned ON during daylight hours. On vehicles manufactured for domestic markets, the odometer VFD is also illuminated at full brightness whenever the MIL indicator is illuminated, and cannot be dimmed until the MIL indicator is extinguished.
The odometer VFD unit has several display capabilities including odometer, trip odometer A and B, gear selector indication (PRNDL) for vehicles with an automatic transmission, several warning or reminder indications, and various diagnostic information when certain fault conditions exist. On vehicles not equipped with the optional CMTC, the odometer display toggles to an outside temperature display following Trip B. The CMTC VFD unit displays numerous warning or reminder textual messages, all CMTC data including compass, temperature, trip computer, the customer programmable features interface and various diagnostic information when certain fault conditions exist. An odometer/trip odometer select and reset switch on the CCN circuit board is used to control many of the display modes of the odometer VFD unit. This switch is actuated manually by depressing the odometer/trip odometer select and reset switch push button that extends through the lower edge of the cluster lens, adjacent to the odometer VFD that it controls.