Automatic Headlamp System; Lamps On Reminder; Daytime Running Lamps - GMC Yukon Denali 2003 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.
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" under Interior Lamps on page 3-17 .

Lamps On Reminder

If a door is open, a reminder chime will sound when
your headlamps or parking lamps are manually turned
on and your key is out of the ignition. To turn off
the chime, turn the headlamp switch to off or AUTO and
then back on. In the automatic mode, the headlamps
turn off once the ignition is in LOCK and the headlamps
on at exit delay ends (if enabled in the DIC).

Daytime Running Lamps

Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short
periods after dawn and before sunset. Fully functional
daytime running lamps are required on all vehicles
first sold in Canada.
3-15