CTS-V V8-6.0L VIN U (2006)
License Plate Lamp: Description and Operation
LICENSE LAMP
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 tail lamp assemblies wrap around the corner of the vehicle and serve as the rear side marker. The lower portion of each 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 and use an incandescent bulb. 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 fuse block
underhood 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 on 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
LIC/Dimming fuse, LT PARK fuse and to the RT PARK 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 dimming fuse supplies battery positive voltage to the license lamps, underhood lamp 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.
