you could check fuse # 11 under hood fuse box. otherwise, there is a door in front of the tire on the inner wheel well. one phillips screw. you should have access to the back of the head lamp assy. hope this helps.
L & R low beams are separately fused. As Yellow Bear points out #11 is the Driver side low beam fuse.
Turn on your headlights, if low beam is out then its either the fuse or the bulb.
If both DRL are inop and headlight low beams are OK then the DRL diode is shot. It is located in the black box on the bullhead in the roof storage compartment. The diodes are still available from GM since they were used on several models. The replacements mounting bracket may be slightly different if not and SSR replacement but can be made to work.
Also make sure the fuse fits tight in the slot. mine was loose and right Low beam was intermittent. I twisted the tabs on the fuse with pliers and reinserted, problem fixed.
The door in the Wheel well to access the bulb has 7mm hex head on it if OEM which is a very unusual size, a 1/4" socket will work in a pinch. Turn the wheel hard right to get room to get at the panel in the drivers side wheel well.