All Lights On Trailer Work Except Brake Lights Even with Weak Ground on 2006 Dodge Sprinter RV

Question:

I have a 6 pole connector.all lights on trailer were working fine last time out.Hooked up next trip and brake lights didnt work all outher lights ,turn signal,Running lights worked fine. Now comes the wierd part after unpluging trailer. I checked the ground on the pig tail no ground how did any of the lites work on the trailer?This on a winabaggo motor home 2006 dodge sprinter 3500 chaise.

asked by: Bill D

Expert Reply:

There may have been a slight weak ground that was allowing some of the lower power draw functions to still work. Trailers can sometimes seem possessed when there is a ground issue. So hopefully you have fixed that issue. The grounds on both the trailer side and the vehicle side, as well as the grounds for all of the trailer lights will need to be attached to clean and corrosion free bare metal surfaces.

A weak ground issue would show up as soon as there is higher power draw on the system. Brake lights light up brighter and require more power so that is when the issue showed up. Making sure you have good, clean grounds and trailer and vehicle side connectors should fix you up.

I have included a link to a couple of FAQ articles that should help you.

expert reply by: Michael H