Hummer 2010 H3 - Manual (Page 148)

6-4 Lighting
The DRL system comes on when
the following conditions are met:
. The ignition is on.
. The exterior lamps control is
in AUTO.
. The transmission is not in
P (Park), if the vehicle has an
automatic transmission.
. The light sensor determines it is
daytime.
When the DRL are on, no other
lamps are on. The instrument panel
will not be lit up either. For vehicles
first sold in Canada, if parking lamps
are manually turned on, DRL will
stay on.
When it begins to get dark, the
automatic headlamp system
changes from DRL to the
headlamps.
The regular headlamp system
should be turned on when needed.
To turn off the DRL, see Exterior
Lamp Controls on page 6‑1.
Vehicles first sold in Canada
cannot turn off DRL unless certain
conditions are met. See Exterior
Lamp Controls on page 6‑1.
Automatic Headlamp
System
When it is dark enough outside, the
automatic headlamp system turns
on after the transmission has been
shifted from P (Park) to D (Drive).
The headlamps, taillamps,
sidemarker, parking lamps, roof
marker lamps, and the instrument
panel lights turn on at normal
brightness. The radio lights will
become dimmer when the
headlights are off compared to
when the headlights are on.
The vehicle has a light sensor
located on the top of the instrument
panel. Do not cover the sensor,
or the system will be on whenever
the ignition is on.
The system can turn on the
headlamps when driving in a
parking garage, through a tunnel or
when there is 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 system 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
detects a change in lighting lasting
longer than the delay.
If the vehicle is started in a dark
garage, the automatic headlamp
system comes on immediately.
Once the vehicle leaves the garage,
it takes about one minute for the
automatic headlamp system to
change to DRL if it is light outside.