4HI and 4LO Status Lamps Outputs

Selector Switch Status Lamp Schematic:

OPERATION
The Transfer Case Control Module (TCCM) controls the operation of the 4HI and 4LO status lamps in the transfer case selector switch. The status lamps also show the transfer case mode and range of operation. The status lamps also provide a self-test when the ignition is first turned on. Additionally, the status lamps are used to alert the driver that there is a problem somewhere in the four-wheel drive system, and also to flash diagnostic trouble codes (DTC's).