I have changed the bulb on both sides and fuse. The high beams work, parking, fog and brake lights work.
Why my low bem lights (running lights) will not come on. on 2005 GMC Envoy
Could be a dimmer switch or relay. Probably would need to be diagnosed by a shop with automotive electrical experience who could review the electrical diagram and map out powers and grounds.
1 more answer
the relay is bad