GMC 2007 Envoy - Manual (Page 180)

Headlamps on Reminder
A reminder tone sounds when the headlamps or
parking lamps are manually turned on, if the
driver’s door is open and the ignition is in LOCK
or ACC. To turn the tone off, turn the knob all
the way counterclockwise.
In the automatic mode, the headlamps turn off
once the ignition key is in LOCK.
Daytime Running Lamps (DRL)
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 DRL are required on all
vehicles first sold in Canada.
The DRL system makes the headlamps come on
at reduced brightness when the following
conditions are met:
• The ignition is on.
• The exterior lamps knob is in automatic
headlamp mode.
• The light sensor detects daytime light.
• The transmission is not in PARK (P).
When the DRL are on, only the headlamps will be
on. The taillamps, sidemarker and other lamps
will not be on. The instrument panel will not be lit
up either.
When it begins to get dark, the headlamps
automatically switch from DRL to the regular
headlamps.
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