Automatic Headlamp System; Puddle Lamps - GMC Yukon XL Denali 2005 Owner's Manual

Automatic Headlamp System

When it is dark enough outside and the headlamp switch
is in AUTO, your automatic headlamp system will turn on
your headlamps at the normal brightness along with other
lamps such as the taillamps, sidemarker, parking lamps,
roof marker 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.
Your vehicle has a light sensor located on the top of the
instrument panel. Be sure it is not covered, or the
system will be on whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. 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 will only be affected when the light sensor sees a
change in lighting lasting longer than the delay.
3-16
If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once you
leave the garage, it will take approximately one minute for
the automatic headlamp system to change to DRL if it is
light outside. During that delay, your instrument panel
cluster may not be as bright as usual. Make sure your
instrument panel brightness control is in the full bright
position. See Instrument Panel Brightness on page 3-17.

Puddle Lamps

Your vehicle may be equipped with puddle lamps to
help you see the area near the base of the front doors
when it is dark out. The puddle lamps will illuminate
when a door is opened, or when you press the unlock
button on the keyless entry transmitter. The lamps
will time out or turn off once the engine is started.