Commander 2WD V6-3.7L (2009)
Tachometer: Description and Operation
Tachometer - Description
DESCRIPTION
A tachometer is standard equipment on all instrument clusters. The tachometer is located to the right of center in the instrument cluster, between the
speedometer and the coolant temperature gauge. The tachometer consists of a movable gauge needle or pointer controlled by the instrument cluster
circuitry and a fixed 210 degree scale on the gauge dial face that reads left-to-right from 0 to 7. The text RPM X 1000 imprinted on the cluster overlay
directly above the hub of the tachometer needle identifies that each number on the tachometer scale is to be multiplied by 1000 rpm.
On all vehicles the tachometer graphics are gray and white against a black field except for several red graduations at the high end of the gauge scale.
In all base vehicles, the gauge graphics are clearly visible within the instrument cluster in daylight. When illuminated from behind by the panel lamps
dimmer controlled cluster illumination lighting with the exterior lamps turned ON, the white text and graphics still appear white, the gray graphics still
appear gray and the red graphics still appear red. The red gauge needle has internal optical illumination. Gauge illumination is provided by Light
Emitting Diode (LED) units soldered onto the instrument cluster electronic circuit board.
In all Limited and Overland vehicles, the gauge graphics are nearly invisible within the instrument cluster in daylight while the ignition switch is in the
OFF position. When the ignition is turned ON the gauge is illuminated from behind at full brightness by the cluster illumination lighting. The white text
and graphics still appear white, the gray graphics still appear gray and the red graphics still appear red. The white gauge needle has internal optical
illumination. With the exterior lamps turned ON, the cluster illumination lighting is panel lamps dimmer controlled. Gauge illumination is provided by
LED units soldered onto the instrument cluster electronic circuit board.
The tachometer is serviced as a unit with the instrument cluster.
