Trailer Lights pulse

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

I connected the trailer to my wifes SUV with factory installed tow package, same results. I ran Ancor 14 ga wire from the ground point on tongue back, spliced it to two wires, then to side marker and back to taillights, same results. With brake on and left turn, right dims slightly when turn comes onand vice versa. I greased all bulbs and the TV conecter. I also replaced TV converter soldering each connection. What gives? I am going nuts trying to get this right, the old lights did not do this, am I missing something or are the lights just cheap junk? Blazer International brand. Grrr. I think I may have wasted my time and money on these, at least my soldering skills have improved!!!

I also cleaned the TV battery positive post.

Jeremy
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
17,072
Re: Trailer Lights pulse

Diming and flash back is a ground issue. You proved that when both trucks did the saem thing
A clean ground to the trailer frame means nothing if the ground isn?t solid and continuous from the bulb to the battery. Run a ground wire from the battery directly to the lamp and see if that doesn?t resolve the issue.
 

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

Diming and flash back is a ground issue. You proved that when both trucks did the saem thing
A clean ground to the trailer frame means nothing if the ground isn’t solid and continuous from the bulb to the battery. Run a ground wire from the battery directly to the lamp and see if that doesn’t resolve the issue.

Ugh,what a pain this is. I will try running a ground from battery back. I may just exchange the lights for the LED version.

Jeremy
 

Wind dog

Petty Officer 1st Class
Joined
Aug 13, 2012
Messages
304
Re: Trailer Lights pulse

I'm with the bad ground group. I never trust the hitch to be a good ground, allways run a ground wire from lights through the plug & ground to the frame of the TV.
And yes paint the bare spots, You will be protecting the connections, though if you take the advise here you will be grounding through the plug & directly to the TV.
You'll have the same problem with the LED's if you don't fix the ground issue.
 

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

Ok so, I ran a 14 ga wire from battery ground to Left tail on trailer ground. Brakes are on and right turn, left brake light still dims, but get this, I totally removed the ground from the light and held the light in my hand, the bulbs dimmed but still were on! How can it work when there is no ground at all??? Colors on wires are correct, what is going on here? TV was hooked up and running.

Jeremy
 

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

One more layer to add. I disconnected all grounds and un bolted all lights, they are hanging free of everything. I set my ohm meter to 200 range, one probe in ground and check the three others, open circut. move one probe to tail and check to Right turn/stop I get a reading of 6.3, checked the next two with the same or similar results, now I'm no electrician but I would think there should be no continuity between the three "live" wires, tail, right turn/stop, left turn/stop. With all the gounds disconnected none of the live wires has continuity with the trailer. Bad molded plug on the new wire harness possibly?
 
Joined
Feb 17, 2012
Messages
2,906
Re: Trailer Lights pulse

i can not see a problem with that, remove the bulbs and it will read open.

note you only have one ground from the light to the trailer for 2 bulbs so the grounds are linked in the light
 

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

i can not see a problem with that, remove the bulbs and it will read open.

note you only have one ground from the light to the trailer for 2 bulbs so the grounds are linked in the light


I realized that after posting, but thank you. I still don't understand how when NO grounds are connected and the brake on TV are on the trailer lights come on very dim, is the current backing through the turn signals somehow?

Is it possible the lights are just drawing to much jucie? Small diameter poor quality wire be the culprit? Would it be possible that LED's with their low draw resolve the issue? I do feel confident the ground is good, especially with the addition of the 14 ga to supplement the trailer frame itself and the fact that when I ran a 14ga wire directly from TV battery to the light that was dimming.

Thanks everybody
Jeremy
 

batman99

Petty Officer 1st Class
Joined
Sep 13, 2012
Messages
393
Re: Trailer Lights pulse

.

Sounds like the problem is staying with the trailer (your trailer).

As a suggestion, remove the removable bulbs from all sockets. If one of their bases shorts out, it will "back feed" into other wires. Especially in the large light assemblies - that contain both running & Turn/Stop light bulbs.

Starting from scatch:
- Print diagram at http://rv-mobile-services.ca/wp-content/uploads/2011/10/wiredtrailer.jpg
- Overlay onto your trailer colors. For example, might be red wire on your trailer and green wire in the diagram.
- With all socket bulbs remove, let's focus on one trailer bulb at a time. For example, get its clearance/running lights stable. Then, remove its many bulbs and focus on the next color wire. For example, the Left Signal wire. Then the Right signal.

Long mumblings short.... Can you get the clearance/running lights working "1 bulb re-installed at a time"? Can you get LS/Brake wire working "1 bulb at a time"? etc. etc.

Hope this virgin approach helps as well...
 
Joined
Feb 17, 2012
Messages
2,906
Re: Trailer Lights pulse

I realized that after posting, but thank you. I still don't understand how when NO grounds are connected and the brake on TV are on the trailer lights come on very dim, is the current backing through the turn signals somehow?

Is it possible the lights are just drawing to much jucie? Small diameter poor quality wire be the culprit? Would it be possible that LED's with their low draw resolve the issue? I do feel confident the ground is good, especially with the addition of the 14 ga to supplement the trailer frame itself and the fact that when I ran a 14ga wire directly from TV battery to the light that was dimming.

Thanks everybody
Jeremy

with no ground connected the light will still light as it will back feed which is what we all thought the problem was in the first place as that normal. you tried another set of lights on the tv and they did the same thing which surgests the tv then you tryed a diffrent truck and you got the same results.....dam thats just bad luck. i even made a sketch of the lights to see what back feed is possible but it looks like all bases are covered like poor connection on bulbs, poor grounds, etc. the only time i have seen something like this was when a hazard light switch was playing up in the truck but that was a easy spot as the lights on the truck were doing the same thing. 2 sets of lights on 2 diffrent trucks doing the same thing is a puzzle. the light dimming with the brake peddle and indicator running at the same time sounds like a voltage drop especially if you have a isolated relay on the tv with a seperate feed from the battery. but that wouldnt explain why the wifes truck did the same thing. l.e.d lights might fix the problem as there amp draw is alot lower but i hate to use a new part until its proven that the old one has a problem.
 

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

I hate to replace a part too, but I don't know what else to do. Its possible the TV isn't putting enough power to the trailer, or the thin gauge harness isn't passing enough, or the lights themselves are bad. I can exchange the incandescent ones for LED, so that will be my next step. Got a 6 hour trip coming up and I'm now running short on time. Always something.

Jeremy
 

Snowfish

Petty Officer 1st Class
Joined
Jul 3, 2009
Messages
234
Re: Trailer Lights pulse

Its possible the TV isn't putting enough power to the trailer
Jeremy

Yes, very possible. I've test a tow vehicle, with a LED plug in circuity tester, and all checks out. Then I've connected my "vehicle simulator box", to the trailer, and all works great.

Plug the tow vehicle & trailer together and nothing. Test seperate again, good. Plug trailer and tow vehicle together and nothing.

Reason? It doesn't take much to light the LED's on the vehicle tester. I Does take a bit of juice to light the trailer though.

Solution? Get a trailer light converter that draws power directly from the battery. Like this one.

http://www.trailerpartsusa.com/products/LM-46365?gclid=CN285Kac27ICFfBcMgodNmQAuA

Then you're sure to have enough juice to light any trailer light system.
 

Jhayes

Cadet
Joined
Sep 26, 2012
Messages
15
Re: Trailer Lights pulse

New LEDs all the way around, bingo! Perfect function. Same wire harness and 14ga ground wire run to each light. What a pain, I should've bought LEDs the first time around. I still am not sure what was up with the other ones but am betting a light gauge harness wasn't helping. Thanks to all for the help.

Jeremy
 

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,398
Re: Trailer Lights pulse

Glad it all worked out in the end. My money was on the electrical power coming through in lumps !!! :D
Either that or it only did it when you were playing 70's dico music on the car audio equipment. :D

By the way, I have been following this thread but had nothing to add to what anyone else was saying already.
 

aburke120

Petty Officer 2nd Class
Joined
Jun 27, 2011
Messages
187
Re: Trailer Lights pulse

I'm confused. Are the new led's just bulbs, or are they in a new fixture. Everything that's been written above would lead to a bad ground. I just took my river boat out of storage and none of the lights worked until I redid the ground on the trailer pigtail, now everything is working and very bright. I agree with Wind dog about the same problem without fixing the ground. Sounds like FM to me.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,796
Re: Trailer Lights pulse

I am sure there is still a ground issue. Since LEDs use a lot less current than a regular bulb, you don't see the same voltage drops. Eventually, that bad ground will get worse and the OP will be back with why his LEDs are getting dimmer.
 

Wind dog

Petty Officer 1st Class
Joined
Aug 13, 2012
Messages
304
Re: Trailer Lights pulse

I'm confused. Are the new led's just bulbs, or are they in a new fixture. Everything that's been written above would lead to a bad ground. I just took my river boat out of storage and none of the lights worked until I redid the ground on the trailer pigtail, now everything is working and very bright. I agree with Wind dog about the same problem without fixing the ground. Sounds like FM to me.

In my experiance they are complete light assemblies.
 
Top