So I get in the truck, start it. Then turn on the park lights and they go out. Ok so I just change the fuse. Happens again, and again. Then I just fiddle with the harness underneath and now its all better. During the day its not so bad without park lights. But at night its really dangerous, people coming up behind you can't really see you that well. Is it a ground thats causing this problem?

Thanks
Geoff