Why can't I get a ground on my trailer ?

[Scottintexas]

last time I pulled my trailer I noticed I had a light issue,
all marker lamps worked
only right tail light worked, no stop or turn signal
no left tail, stop or turn signal

I had remembered last year I didn't have a light or two but just chalked it up to a burnt bulb and was going to replace them later. Well now is the time,

I made sure I the 5 pin on the truck was working correctly and sending power.

I bought a new LED unit and cut the old left light assembly off temporarily connected the new LED and now I have no lights at all, no makers or right side either. I tried the old assembly on a 9v battery and they still did not work so I feel confident the sealed unit is bad.

I ran a direct ground wire from the grounding point at the front of the trailer where the 5pin connector grounds to and the LEDs work, I also pulled the first marker light and hooked up the direct ground and it worked also.

I took some sandpaper and shined up surface where the ground was previously attached at the rear but that didn't help.

Why did I loose all my lights units when they are each grounded separately?

Why can't I get a good ground at the rear of the trailer when I even sandpapered the painted surface to bare metal?

any help would be greatly appreciated,

 

[sysinu]

test it with a voltmeter or continuity tester. My guess is that you are getting ground but that you have a short between ground and 12VDC. Have you tested it with a separate 12V battery? I had this issue with my last boat whenever the running lights were on everything went out. It had turned out to be a light wired backward by the previous owner.

 

[jetboater4life]

Are you sure you getting a ground through the folding tongue. The ground goes through the hinge and can be problematic at times. Some have wired a wire around that to guarantee a good connection and others have run separate ground wires all the way through the trailer frame to each light.

 

[itsdgm]

Are you sure you getting a ground through the folding tongue. The ground goes through the hinge and can be problematic at times. Some have wired a wire around that to guarantee a good connection and others have run separate ground wires all the way through the trailer frame to each light.

X2

The hinge in the folding tongue isn't a good conductor. Especially after a few years of use. I ran a ground wire from the original ground spot, through the folding tongue and reconnected the other end to where the first marker light on the side of the trailer in grounding to the frame. That solved my grounding issues.

 

[Gym]

@Scottintexas. Your power & ground come from your tow vehicle through your 5 pin connector. There is a ground wire attached directly to your trailer near the hitch. You should be able to go from that ground wire to a non painted metal part on your tow vehicle with an ohm meter and see continuity. Then you should be able to go from the trailer frame to the tow vehicle and also get a good reading. I suspect the test from the frame to the tow vehicle will show an open or a poor ground as it's affecting ALL your lights. By the way, a short would blow a fuse ONLY on the power side. It would not affect your ground so if you are getting power and no ground you have a broken ground wire.

 

[Scottintexas]

X2

The hinge in the folding tongue isn't a good conductor. Especially after a few years of use. I ran a ground wire from the original ground spot, through the folding tongue and reconnected the other end to where the first marker light on the side of the trailer in grounding to the frame. That solved my grounding issues.

Thanks guys, I ran a pig tail from 5pin ground near the hitch to the grounding screw for one of the marker lights and they all worked. I must have lost ground in the hinge of folding tongue, I will run a permanent jumper as Dennis did,

 

[Scottintexas]

Thanks again for the quick responses so I could work on it today, new LED's are finished, I ran a permanent jumper for the ground around the tongue hinge onto the first marker and have both new LED's hooked up and everything works great. It feels good to be legal and safe again!