GMC Sierra Owners Manual
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for others to see the front of your vehicle during the day.
Fully functional daytime running lamps are required on all vehicles first sold in Canada.
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 Park.
• The light sensor determines it is daytime.
When the DRL system is on, only the DRL lamps are on. The taillamps, sidemarker, instrument panel lights, and other lamps will not be on.
When it begins to get dark, the automatic headlamp system switches from DRL to the headlamps.
To turn off the DRL lamps, turn the exterior lamps control to the OFF position and then release. For vehicles first sold in Canada, the transmission must be in the P (Park) position before the DRL lamps can be turned off.