I need help with a wiring issue I’m having.
Took delivery and assembled a 4x6 Carry-On trailer Friday. Today when I got it hooked up I was only getting the driver side front running light. I check the 4-pin connector at the vehicle side with a tester and everything is working just fine. I redid the ground on both the vehicle and trailer side and they’re both getting very good metal to metal contact. I can’t figure out why only the 1 light is working. Iv tried everything I can think of and spoke to an 30+ year electrical engineer and we’re both stumped. Any ideas?