
Black plate (4,1)
GMC Yukon/Yukon XL Owner Manual - 2012
6-4
Lighting
When it begins to get dark, the
automatic headlamp system
switches from DRL to the
headlamps.
To turn off the DRL lamps, turn the
exterior lamps control to the OFF
position and then release. For
vehicles first sold in Canada, the
transmission must be in the P (Park)
position before the DRL lamps can
be turned off.
Automatic Headlamp
System
When it is dark enough outside, the
automatic headlamp system turns
on the headlamps at the normal
brightness, along with the taillamps,
sidemarker, parking lamps, and the
instrument panel lights. The radio
lights will also be dim.
To turn off the automatic headlamp
system, turn the exterior lamps
switch to the off position and then
release it. For vehicles first sold in
Canada, the transmission must be
in the P (Park) position before the
automatic headlamp system can be
turned off.
The vehicle has a light sensor
located on the top of the instrument
panel which regulates when the
automatic headlamps turn on. Do
not cover the sensor, otherwise the
headlamps will come on whenever
the ignition is on.
The system may also turn on the
headlamps when driving through a
parking garage or heavy overcast
weather. This is normal.
There is a delay in the transition
between the daytime and nighttime
operation of the Daytime Running
Lamps (DRL) and the automatic
headlamp systems so that driving
under bridges or bright overhead
street lights does not affect the
system. The DRL and automatic
headlamp system are only affected
when the light sensor detects a
change in lighting lasting longer
than the delay.