RAM 2500 Truck 4WD V10-8.0L VIN W (1997)
Four-Wheel Drive (4WD) Indicator Lamp: Description and Operation
SYSTEM OPERATION
On models equipped with the four-wheel drive option, a four-wheel drive indicator lamp in the instrument cluster lights any time the front axle is
in the four-wheel drive operating mode. Ignition switched battery voltage is supplied to one side of the indicator lamp bulb. A switch on the front
axle disconnect housing is hard-wired to the other side of the indicator lamp bulb.
The normally open, plunger-type, four-wheel drive switch is threaded into the front axle disconnect housing. The switch is connected in series
between the indicator lamp bulb and ground. The plunger of the four-wheel drive switch is actuated by the front axle disconnect shift fork when
the vacuum-controlled front axle disconnect mechanism is actuated, opening or closing the switch and the ground path for the indicator lamp.
CIRCUIT OPERATION
Power for the four-wheel drive indicator lamp is supplied on circuit F14. Circuit G107 connects the lamp to the four-wheel drive switch. When the
switch closes, circuit G107 connects to ground on circuit Z1.
