Sierra 1500 2WD V8-5.3L VIN Z Flex Fuel (2006)
Map Light: Description and Operation
READING LAMPS
The inadvertent power supply voltage circuit of the BCM provides battery positive voltage to the reading lamps. The reading lamps and switch are
integral to the courtesy/reading lamp assembly. When the switch is closed, voltage is supplied and the lamp illuminates. In the event that any of these
lamps were to remain illuminated for a period of more than 10 minutes with the ignition switch in the OFF position, the BCM will deactivate the
inadvertent power supply voltage circuit to prevent a total battery discharge condition. Ground is provided to the reading lamps at G203.