TROUBLE WITH LIGHTS

GA_Boater

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What Jeep do you have? Does it have amber turn signals and a factory tow package?

Can you try plugging into another tow vehicle?
 

Government cheese

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I had trouble with the lights on my brother's camper. The issue was the frame grounds were all bad. I ended up welding a bolt to the frame near the tongue and ran all the grounds from the lights to that bolt, then to the white of the plug. Everything was then sealed up. Now everything has a did ct line to the ground, and if there is something that s frame grounded, it is grounded as well.
 

Government cheese

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I think you have bad grounds. Either run a fresh ground wire from each light to a common bolt, and then to the ground wire of the plug, or take your grounds apart and grind the rust and paint off so you have a clean connection. Trailer company's es ground to the frame because it is cheap and easy, but it doesn't work for long.
 

smokeonthewater

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It's the grounds... It's almost always the grounds.

Go pick up a roll of wire long enough to reach from a good ground on the jeep to the back of the trailer and test.... I bet ya a dollar the lights work perfect when the solid ground is run to them.

The reason you get goofy readings on your turn signals is because they are flashing... Have someone hold the brake pedal and you'll get a good reading.
 
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JAL51974

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The jeep is a 2004 grand Cherokee factory tow package. I'm getting good power and grounds on the jeep side. I cleaned and sanded all the grounds on the trailer when I installed these new LED lights too. If there is a converter where do I find it?
 
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JAL51974

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The test I'll run tonite is using this old trailer harness plug seeing what voltage I get at the wires on the tail. By elimination if i get good readings at these wires then the problem is in the LEDS. Because I have good power from the jeep and I know the trailer plug is good too by previous tests from yesterday. And the wires from tongue to tail are new straight runs I haven't spliced in any side markers yet.
 

2 Eagles

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You have a bad grounds. Try claening the ground screw hole and all around the screw hole, and check all the grounds at the lights. Or wire the ground to the lights.
 
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jbcurt00

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JAL this is still all about your trailer lights, I combined the 2 topics.

Try not to start 2 topics about the same project or problem, it just means you'll have to repeat info you provided elsewhere when someone asks questions or requests pix of whats been done prior to where the 'new' topic starts

Thank you
 
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poconojoe

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My trailer harness has a ground wire throughout. Every light has a ground wire. They do not get their ground from the frame.
As others have said, whenever you get weird or intermittent readings, it's most likely a ground problem.
 

JAL51974

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OK thanks for combining these two topics.
Tonite I will also run a separate ground wire from the Jeep to the two tail lights and see what results. I will keep you posted. Thanks. Joe
 

JAL51974

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I should have listened closer to you guys earlier and it would have saved me a LOT of time and aggravation. I tested the voltage at the tail lights and it was around 5V. But once I hooked up only one continuous ground wire from the ground screw at the tongue to the tail lights they both lit up and turn signals and emergency flasher worked fine. So this was a case of phantom wire problems being the faulty ground on the trailer. I hooked up one side tonight and will finish the rest tomorrow night. 'Thanks for all the help. Joe
 

GA_Boater

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See - It's almost always a ground. I'm glad because I haven't figured out if you have or where the convertor would be. Now I can stop looking. :smile:
 

smokeonthewater

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Glad you got it.

Trailer light problems are:
49% Bad grounds
2% Misc other issues
49% Bad grounds
 
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JAL51974

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We took it out last weekend with the grandkids and everyone had a great time! Those lights lit up like a Christmas tree!!
 

seadogmike

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If you have the 4 pin flat connector, check the connector itself. I replaced one on my Dodge Pickup once, and after about 3 weeks, started having light issues again. I found out that the white wire was broken up inside the connector. It was a walmart cheapie connector kit. Replaced it with a kit from NAPA.... Problem solved.
 
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