Wrangler 4WD V6-3.8L (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 185 degree scale on the gauge dial face that reads left-to-right either from 0 to 7 for vehicles with a gasoline engine, or from 0 to 5
for vehicles with a diesel engine. 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.
The tachometer graphics are white and gray against a black field except for several red graduations that designate the red line area at the high end of the
gauge scale, making them 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 and gray text and graphics still appear white or 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.
The tachometer is serviced as a unit with the instrument cluster.
