I hooked up my trailer today and I have no marker lights. I have a 2008 hummer h3, alpha. Brake and signal lights work. Anyone know if this is an easy fix? If it's a fuse, which number? I looked at a few today and none were blown. I tried to find 55 but couldn't see it. Please help, thx

 

Did you check the 7 pin connector on the H3 for marker light power (#3)?

If your rig is has power at the connector #3 position and the lights are not working on the trailer. It's the wiring of the trailer that is at fault. Any bulbs or fixtures damaged on the trailer?

You can also feed #3 power and #1 ground to see if the trailers lights work. If they work, it's the rigs wiring.