GMC 2005 Automobile User Manual


 
If you release the parking brake, the lights will turn on.
If the parking brake is not released before you
begin to drive, the exterior lamps will turn on above
2 mph (3.2 km/h).
Your vehicle is equipped with a light sensor located on
the top of the instrument panel in the defroster grille.
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 bright enough 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 3-18.
To idle your vehicle with the automatic headlamp system
off, turn the control to the off position.
You may be able to turn off your Automatic Headlamp
System. See “Daytime Running Lamps (DRL)” later
in this section for more information.
Your headlamps will also stay on after you exit the
vehicle. You can program this feature using the Driver
Information Center (DIC). See Driver Information Center
(DIC) on page 3-52.
As with any vehicle, you should turn on the regular
headlamp system when you need them.
3-16