I drive a 2011 Sierra 3500HD and I am having an issue with my headlights. First I was going through lights about every 20,000 miles. Now my headlights will not come on at all. I changed the headlight switch and the bulbs. Neither of these worked. I checked the fuses and they are good. My marker lights and my high beams work. Is their a relay I should look for? What do you recommend.
