Trailer Lights Freaking Out, any ideas?
 

Okay, here's what happened going home tonight. When I turn the truck lights on the trailer lights come on. When I hit the brakes, the rear trailer lights go out. When I hit a turn signal or the flashers the rear light/lights go on and off, not on and then get brighter. I have a 01'Dodge with the factory trailer plug that the boat trailer light plug plugs into. Did that make sense?

In other words, the factory plug can only plug in one way because of the little rectangle "key" and the trailer lights can only plug into it one way because of the typical I male/3 female "contacts".

With the truck lights off, when I hit the brakes, turn on a turn signal, or hazard, nothing.

Any guesses?

I hate electrics.........

Sounds like the ground is reversed somewhere. Its not hard, but I think you are going to have to stick the a meter on the plug on the truck, and make a harness; or did this JUST start happening?

You may just have a bad ground OR if you have changed lights recently make sure you did not put them in wrong or put the wrong bulbs in.

Jon

I had the same problem with an old trailer. I redid all the grounds. If you installed new lights make sure they are grounded properly.

Sounds to me that you have a couple of blown bulbs. They are double element and will show running lights but no turn or brake lights. Check the bulbs first then the grounds

get a dog like mine, then you wont have any lights to worry about :D

Sounds like a bad ground or just bad connections. I solder and shrink tube everything. If you have the crimp type connectors on the trailer, that would be the first place to look.

Definatley a bad ground. If the wiring on the trailer is old and crapy don't even mess with trying to find the bad ground. Rip all the wiring off and start from scratch. I know it sounds crazy, but in the long run it will save you alot of headaches.

What he said!:D

Sounds like they are operating properly. I think that trailers are shipped from the factory with lights like that!:D

Try plugging it up without the trailer on the truck ball and see what happens. If it gets worse or they don't work at all then you know it's a ground issue.

.02

Check the plug on your truck for power. Make sure that the problem is not with the truck. I have had the same type of setup on my Z71 for one year and granted we go through winter up here the but the wires had broken off. If you have power from your truck, then I agree that it is either a bad ground or possibly a 2 - stage bulb that is burned out.:hothead:

Check your ball for excessive rust, some trialers ground out thru them. Also if you have replaced any lights make sure the grounds and on metal not just paint itself. If it is a 6 way or 7 way plug take the set screws off and check to see if any of the wires in the plug end came loose. If your truck dosent have a ground going thru the plug add one there to match the trailer plug. If you have to strip all the wiring its not that bad, you can buy the whole harness from any trailer shop or do the light kits from wallmart and leave the lights out of it.

sounds like a bad ground to me

Just stop and isolate the problem to truck or trailer.
Test the truck signal first with a volt meter. Make sure you're getting the juce when you should be.

Than look at the trailer. But it's probably the trailer lights.

I just threw out the standard lights from my trailer and put on a nice set of LED lights... MUCH better.

I got sick of worrying about grounds on all of the different trailers I pull so I just ran a three foot ground wire from the tounge of all of them, including goosenecks, and a four inch stub wire on the hitch. I might sound dumb but I have not had a problem with a ground since.

:rolleyes: I checked the bulbs, that was my first thought, though I thought blowing both bulbs at the exact same time was a little odd. Bulbs are okay. My trailer does not grounds through the trailer hitch, it grounds through the plugs. What I don't get is why is the ground good enough for the side lamps and tail lights to work, but not the brake light filiments. When I turn the lights on, the lights on the trailer seem "brighter' than normal. Or maybe I'm just losing my mind, I don't know. Good idea about checking where the Dodge plug plugs into for power, then checking the "out" side of the Dodge plug for power (where the trailer plug plugs into). Thanks guy. It's comforting to know help is just a keyboard away.

sounds like the blinker fluid.. or the exhaust belt

Damn, forgot about that blinker fluid.

LOL :D

i think it's a ground wire.. mine.. I'd push on the brakes and it would cut the radio out int he truck.. :eek:

I just love trailer light electrics.....Nothing makes any sense.....EVER..... :crazy: :crazy:

Most likely bad ground.

On some vehicles the brake wire is grounded when not lit. Here's what happens case where you have a bad ground. 12 volts is on one side of the running light element in the bulb, there is no ground on the ground side of running light element (bad ground). The ground side of the running light element and the ground side of the brake light element are tied together in light fixture. Since the hot side of the brake element is grounded when not in use, ground is going through the brake element to ground the running light element. Both elements of the bulb are usually lit when the lights are on.

Remember that the ground is being supplied from the hot side of the brake element, well when the brake pedal is pushed, it removes the ground and put 12 volts on the brake element like it should, but now there isn't a ground for either element and all the lights go out.

Since there is no ground, I would be getting in the boat.:D

here is your source for the blinker fluid

http://www.kalecoauto.com/

:D :D

I would start over. I would tie the new wire to the old and pull it through so you can start over. It is a ground, the best way to know is the lights going out with the brakes on. There is no way of chasing down the problem without either making it worse, make a small problem that does not show yet worse, chasing problems like this can be endless unless you start over. In short, I would start over.:D Plus you are in salt and a wire could be bad in the middle from salt wicking up the wire and breaking the current. Now that I see where you are from there is no choice but to start over.

A new set of "LED" lights, and I'll be "starting over".

Yes those LEDs are cool. Go to an underground sprinkling company and get the grease boots they use to connect wires for underground use, they are packed with die electric grease and will never crowd. I have a snowmobile trailer and I used these to replace the lame clips they used. Salt and copper means green dust over time, a short time.

outlaw sed "My trailer does not grounds through the trailer hitch, it grounds through the plugs"

That's what I'm trying to prove, whether the plug ground is good.

Thanks for the suggestion, that is a strong starting point.

It is a bad ground.

If you have narrowed it down to the tail markers, that wire color is brown unless altered. test it with the truck and trailer connected at the tongue then test at the lights this will give you an idea of a brak or not in the system if the test light dosent light up at the lights. Also check the truck plug first before you continue to the trailer.

thanks everyone......

JUST MY 02

Trailer lights absolutely suck.I own 5 trailers, 4 for work and 1 for the boat. Whenever I buy a new trailer i tell them not to wire it. When I get it home i wire the trailer myself. What you want to do is get 12-3 insulated trailer wire. This is the kind that has the rubber casing around all three wires. DO NOT USE the typical yellow and brown wires which are always exposed. Buy an outdoor waterproof junction box, a 4 or 6 pole trailer plug(which ever you use) and solder. Mount the box in the front of the trailer. Bring the wire that will be the trailer plug out the front and two others out the back. Run one piece down the port side to the rear of the trailer and one down the starboard side. Solder the connections for the lights in the back and use the white wire for a ground on the back of the light. Solder all the connections in the junction box and wrap in tape. If you have lights on the sides of the trailers run a separate feed for those. Do not tap into the main brake/directional feed for side running lights. Put the new plug on the truck side and your done. This way there is only one connection box for all the lights. Also , silicone the ends by the lights where you have to cut the rubber insulation so water won't get inside when you back it in the water. This may sound a little overkill ,but i'm a little anal and it works.

Impulsive, you are SO right about the "factor of suckage" regarding trailer lights. You have a great concept for wiring, it sounds great. Thanks a lot.....