trailer lights.

[chopper6322]

i realize that this is pry a simple problem but just don't have any experience with it, just hauled a boat from MI to TX on a used trailer, when we left everything worked, now just the pass. side blinker and brake light work that's it...any suggestions on where to start?

 

[hatch17]

I am assuming all the bulbs still work. I would check all the connections to make sure nothing has come loose, but it sounds like it may be a bad ground wire on the trailer.

 

[chopper6322]

will that one side still work with a bad ground? granted the running lights on the pass side don't work. and i checked the connections, all is good, only discrepency is that it has an adapter from the flat plug to the round one...and the trailer has 5 wires going into the plug and the adapter only has 4, does that matter? also the ground looks good, just a self tapping screw into the trailer frame (is that right?)

 

[hatch17]

A bad ground can do crazy things with trailer lights. It may be that your ground wire is just good enough to handle one side of lights. Undo the ground wire on the trailer and clean the spot to make sure it is touching clean metal for the best ground. Also, each trailer light assembly should be grounded. If your lights are mounted to metal, they are generally grounded when they are screwed in. If the lights are mounted to PVC or wood they won't be grounded the same way, you will need to check to see that they are good and grounded to metal. Also, if you are using a tilt trailer, it could be that the ground isn't reaching the back.

Hope this helps.

 

[chopper6322]

i'm not sure what you mean by tilt trailer, but i'm thinking it may be a bad adapter now...as i play with the connection between the adapter and the trailer the running lights come on and off, but the blinker/brake won't work at the same time as the running lights. also still nothing on the driver side the bulb meters good so i need to try to adapter to see if there is maybe more than one problem....am i correct?

 

[SlimeTime]

Replace connectors & eliminate adapters :wink: Flat 4's only seem to last 2-3 years for me, for $3 for both sides....it's easier to replace them as opposed to fighting them.

Also, if you don't already, learn to solder & use heat shrink.....I've had to repair alot of wiring connections which were either taped, wire nutted, or butt-spliced....solder & heat shrink are the way to go........

ST

 

[chopper6322]

good idea, it's quicker to fix it right once than wrong over and over. i do know how to solder and use heat shrink..thanks and i also like getting rid of the adapter, can i buy a whole light kit with the round connector or will i have to buy and install them seperate?

 

[SlimeTime]

If you have more than 1 trailer, I'd "standardize" everything & make them the same. At one time I switched all mine to the smaller (6 pin I think) round connector, simply because the flat 4's didn't last (but I pulled 3-4 different trailers). I believe the round connectors use setscrews, and don't come as a pigtail, in which case you won't need the solder/heat shrink.

ST

 

[sccamper]

Remember that alot of trailers use the flat 4. If you only pull your trailers your ok. If you might pull someone elses, have a converter back to the flat 4. I made a converter from 7 pin round for camper to a flat 4 so I can have both.