Sierra Classic 3500 4WD V8-6.0L (2007)
Vanity Lamp: Description and Operation
VANITY LAMPS
The inadvertent power supply voltage circuit of the BCM provides battery positive voltage to each vanity mirror lamp. When the vanity mirror cover on
the sunshade is opened, a switch closes to provide a ground circuit and the vanity 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 vanity lamps at G203.