CTS V6-3.2L VIN N (2003)
License Plate Lamp: Description and Operation
PARK, TAIL, LICENSE AND MARKER LAMPS
The tail, stop, and turn signal functions are performed by the quarter mounted tail lamps. The quarter mounted tail lamp consists of a red lens and
incandescent bulbs. The quarter mounted tail lamp wraps around the corner of the vehicle and serves as the rear side marker. The lower portion of the
lamp contains reflectors to alert approaching vehicles for nighttime driving safety. The front park and side marker lamps are part of the front headlamp
assembly.
The park, tail, license and marker lamps are turned on when the headlamp switch is placed in the PARK LAMP or HEADLAMP position or anytime
the headlights are requested. The park lamps are also turned on with the front fog lamps. When the ignition switch is in the ON position, the DIM
provides battery positive voltage to the controlled positive voltage circuit of the PARK LAMP relay coil. The underhood fuse block supplies battery
positive voltage to the switch contacts of the PARK LAMP relay. When the headlamp switch is in the PARK LAMP or the HEADLAMP position, the
park lamp switch signal circuit has ground at G200. In response to this signal, the DIM provides ground to the control circuit of the PARK LAMP
relay coil, which energizes the relay coil. This closes the relay switch contacts. Current flows from the PARK LAMP relay to the RT PARK fuse, LT
PARK fuse and to the LIC/Dimming fuse. From the fuse, the current flows to the park lamps. The front park lamps are grounded at G104 and the tail
lamps are grounded at G401 and G402. The LIC/Dimming fuse supplies battery positive voltage to the license lamps, and to the dash integration
module (DIM) park lamp input, for interior lamps dimming. The license lamps are grounded at G402. The inadvertent power control feature prevents
the park lights from remaining on more than 10 minutes if left on. If the park lights are turned on after the ignition switch has been turned OFF, or is
in the ACCY position, they will remain on until turned off or the battery runs dead.
