Four Wheel Drive Indicator Lamp: Description and Operation

CIRCUIT OPERATION

The Four-Wheel Drive (4WD) Indicator Assembly provides visual information about the operating mode and gear range of the driveline. Voltage is supplied to the IGN/GAU Fuse and Indicator Assembly with the Ignition Switch in START or RUN. The circuit is completed through the Selector Quadrant Switch, which provides a ground path to light various Indicator Assembly Lamps.
With the Selector Quadrant Switch in detent position 1, the "2WHL" Indicator Assembly Lamp is lit.
With the Selector Quadrant Switch in detent position 2, the "4 HIGH" Indicator Assembly Lamp is lit. At this time, the Front Axle Switch is closed and the Indicator Assembly Front and Rear Axle Display is lit.
With the Selector Quadrant Switch in detent position 4, the "4 LOW" Indicator Lamp is lit. At this time, the Front Axle Switch is closed, and the Indicator Assembly Front and Rear Axle Display is lit.
A signal is sent to the Rear-Wheel Antilock (RWAL) Brake Module and the Four-Wheel Antilock Brake Module (4WAL) whenever the 4WD is engaged. This signal turns off the RWAL and 4WAL systems to prevent operation during 4WD operation.