I have a 2005 2 place Aluma trailer and I have never had a problem with it except for the last couple times I've used it, The brake lights and all other lights work well when its hooked up but when I use either signal both the right and left signal will flash in the back of the trailer like the hazards are on. The problem is not in the truck because we have a travel trailer that the lights work fine on. I use a 7 pin to 4 pin connector for the sled trailer and for the ravel trailer I just use the 7 pin. Anyone have any ideas where my problem is?
Need some Trailer wiring help.
- Thread starter slabm7
- Start date
Grab a test light, and find a good ground on your truck (frame, usually). Put the test light in each of your "pins" on your 4 pin connector, and have someone in the truck running the brakes, signals, etc for ya. Failing that, it's likely a ground issue...
A battery charger used as a source works great also (make sure it is set to manual... they don't work in auto for testing things)... makes it more of a one man job as far as testing goes. Test light is the other tool that is needed.
Verify the truck trailer lights circuits are correct, and check your fuses too. I had some weird issues with my trailer running lights going to ground. It took out a fuse in the truck and made all sorts of weird stuff happen.
Took me a while to figure that one out. Best advice I can give you is be very thorough and don't assume anything. Oh, get some paper and a pen to record results too...pin outs of the harness and what not.
Ditto on all the talk about grounds... I was working on a Drott excavator with my old man testing things out... he thought he had a good ground but things weren't testing as they should... I got a 5 foot piece of wire and hit a nice piece of freshly sanded metal.. All of a sudden things started making sense again.
Verify the truck trailer lights circuits are correct, and check your fuses too. I had some weird issues with my trailer running lights going to ground. It took out a fuse in the truck and made all sorts of weird stuff happen.
Took me a while to figure that one out. Best advice I can give you is be very thorough and don't assume anything. Oh, get some paper and a pen to record results too...pin outs of the harness and what not.
Ditto on all the talk about grounds... I was working on a Drott excavator with my old man testing things out... he thought he had a good ground but things weren't testing as they should... I got a 5 foot piece of wire and hit a nice piece of freshly sanded metal.. All of a sudden things started making sense again.
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I think that's where i'm going to start is with a new 7-4 connnector and then start looking at the grounds. Thanks for all your help so far guys.
Most likely a ground problem, I had similar problems last year. Had it grounded on the bed of the trailer. My trailer is a tilt and I had to end up running another wire from the bed of the trailer to the frame of the trailer to get a good ground.
With all the problems of grounds, it makes me seriously consider just wiring grounds to every light... Figure get a bunch of hd extension cords and cut them up for wire. Much more protected then single wires...
For making connections, my old man found through all his years that the best method is to twist the wires together, coat them with silicone and fill a wire nut of appropriate size with silicone, then put the wire nut on the twist. It lasts much much longer, especially in the rain / outdoors / weeds , and the connections aren't out in the air so corrosion stays at a minimum. Just some thoughts...
For making connections, my old man found through all his years that the best method is to twist the wires together, coat them with silicone and fill a wire nut of appropriate size with silicone, then put the wire nut on the twist. It lasts much much longer, especially in the rain / outdoors / weeds , and the connections aren't out in the air so corrosion stays at a minimum. Just some thoughts...
I would also start with the connector had the same problem mine was grounded throught the plug untill it went crazy then everytime you would hit a bump it would loose its ground through the hitch. Replaced the plug no more problems.
I built a trailer harness for a buddy out of a extension cord best idea every. We used aircraft grade splices but the local auto store should have something similar. They are regular butt splices but they come with a piece of heat shrink around them you just splice them and then melt the heat shrink guaranted waterproof.
I built a trailer harness for a buddy out of a extension cord best idea every. We used aircraft grade splices but the local auto store should have something similar. They are regular butt splices but they come with a piece of heat shrink around them you just splice them and then melt the heat shrink guaranted waterproof.
I've used those connectors before, and always have used extension cords. Works like a CHARM.
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