night vision GMC ENVOY 2008 Owner's Manual

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 sees a
change in lighting lasting longer than the delay.
If you start your vehicle in a dark garage, the automatic
headlamp system comes on after the transmission is
shifted out of PARK (P). Once you leave the garage,
it will take about one minute for the automatic headlamp
system to change to DRL if it is light outside. During
that delay, the instrument panel cluster might not be
as bright as usual. Make sure the instrument panel
brightness control is in the full bright position.
If the vehicle is running and the automatic headlamp
system is already on, it can be turned off by turning
and releasing the headlamp control at the off position.
The automatic headlamp system stays off until you
turn and release the headlamp control at the off
position again. SeeHeadlamps on page 3-14.Fog Lamps
Use the fog lamps for better vision in foggy or misty
conditions. The ignition must be in RUN for the
fog lamps to work.
The fog lamp button is
located on the instrument
panel to the right of the
exterior lamps knob.
Press the button to turn the fog lamps on. Press the
button again to turn them off. A light glows near the
button while the fog lamps are on. Fog lamps turn off
whenever the high-beam headlamps are on.
Some localities have laws that require the headlamps to
be on along with the fog lamps.
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Driving at Night
Night driving is more dangerous than day driving
because some drivers are likely to be impaired — by
alcohol or drugs, with night vision problems, or by
fatigue.
Night driving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by adjusting the inside
rearview mirror.
Slow down and keep more space between you and
other vehicles because your headlamps can only
light up so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into approaching headlamps.
Keep the windshield and all glass on your vehicle
clean — inside and out.
Keep your eyes moving, especially during turns or
curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
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