2008 Chevrolet Suburban 1500 LTZ 8 Cyl 6.00L
Why does ONLY 1 daytime running light work??
I have seen brand new, and older suburbans that the driver side drl works but not the passenger side. Even AFTER REPLACING the bulb, its still the same. It seems this is a flaw in the suburbans. Like I stated, I've seen this in absolute brand new , older, and all year inbetween. Infact I've seen 14 suburbans today alone with that situation.
The problem may be the "Daylight Running Lamp Module", try a reset of the module by pulling the "GAUGES" fuse in the Instrument Panel fuse block. Try to find the ground connection (black wire) for the DRL Module, bad grounds can cause some weird symptoms. Check the emergency brake switch and it's ground connection.