I.think I have a bad ground on my trailer but don’t know where to go from here? Lights work when key is not
in the ignition but don’t when key is in or truck is running? I have tried on two vehicles? Any help?
Normally a bad ground will either make the lights flicker with a loose connection or they won’t work at all. If you’ve tried 2 different vehicles with factory trailer light plugs and nothing has been altered with them, it’s definitely in the trailer wiring. I had a similar issue with an old truck and boat of mine and it ended up being a power issue meaning that a power wire is grounding out. Make sure you don’t have any power wires that may have rubbed bare on the trailer or getting grounded out in the light assembly. If all that checks out and is good to go, I would change the plug end on the trailer wires because I’ve seen many contactors in switches break and cause continuous power so the wire terminals may have melted and causing an open circuit. Let me know what you find out, if all else fails, rip it all off the trailer and run new wires from the tongue to the lights.
Sport-Craft 241
Suzuki 225 EFI
In actuality, you do not have to use the white ground wire on a trailer because it will ground through the tongue/ball. However, this is not a great connection, that is why you see lights flickering going down the road. For the lights to work fine when the truck is not running, yet not work when it is on two different vehicles, that would leave me to believe the problem is in the trailer wiring, but I would need to attack it with a meter, because I have never heard of this problem before… odd
Who wired the plugs on the two vehicles, and, are we dealing with a flat 4 plug or a seven wire round using an adapter?
Key West 19’6" CC 115hp Merc
14’ Fast Craft w/ 60hp Merc
It definitely sounds like both vehicles are wired wrong. If they work with the key off and not when its on, something ain’t right in the wiring harness on both vehicles. Do you have a friend with a known good vehicle to check the trailer on?
'06 Mckee Craft
184 Marathon
DF140 Suzuki