Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

Trailer run lights?


  Email This Post



bstruss
Novice

Dec 21, 2014, 4:59 PM

Post #1 of 17 (1509 views)
Trailer run lights? Sign In

I have a weird situation in that my run lights won't work on my utility trailer. There is a 5 to 4 wiring converter prior to the 4 prong trailer hookup plug. Right at the vehicle hookup plug, I can get 12v on the run wire (brown) to ground testing with a meter (the same as the brake lights etc), but I get no current on that wire when I test for DC amps. The turn lights and brake lights work, but there is this weird problem with the run lights.

What could cause there to be proper voltage but no recognizable current? I am guessing an almost open connection somewhere, and wondering if the old U-Haul 5 to 4 converter box might be the culprit? Thanks for any thoughts or suggestions on how to troubleshoot this further.


(This post was edited by bstruss on Dec 21, 2014, 5:12 PM)


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 21, 2014, 5:09 PM

Post #2 of 17 (1502 views)
Re: Trailer run lights? Sign In

No, that converter effects turn and brake lights only. It sounds like you have a problem in the wiring of the trailer. You should be able to power the trailer alone to test that circuit and find out if the problem is in the truck or the trailer.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



(This post was edited by Hammer Time on Dec 21, 2014, 5:10 PM)


bstruss
Novice

Dec 21, 2014, 5:16 PM

Post #3 of 17 (1497 views)
Re: Trailer run lights? Sign In

But I get voltage and no amps testing the run connection to ground testing right at the 4 prong plug (with the trailer disconnected). I do test current on both the turn signal and brake lights. I can see that even though the converter box doesn't split the run light wire, the connection nevertheless passes through it. I am stumped.

What led me back to the vehicle plug, was thoroughly testing the trailer wiring first.

Also, when you say power the trailer alone, how do you recommend doing that without using the current connections?


(This post was edited by bstruss on Dec 21, 2014, 5:20 PM)


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 21, 2014, 5:18 PM

Post #4 of 17 (1492 views)
Re: Trailer run lights? Sign In

You need to stop worrying about current because you are likely measuring it wrong anyway. There will never be any current if there aren't any lights on to consume it.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



bstruss
Novice

Dec 21, 2014, 5:23 PM

Post #5 of 17 (1490 views)
Re: Trailer run lights? Sign In

What led me to measure current, was when I have proper voltage and cannot light a bulb with it (even when hooking a bulb right to this connection with alligator clips). And what do you mean you cannot measure current? I can measure current with my voltmeter at all the other terminals (brakes, turn lights etc) of this vehicle plug?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 21, 2014, 5:27 PM

Post #6 of 17 (1488 views)
Re: Trailer run lights? Sign In

No, you can't. Unless you are interrupting the circuit and pulling the meter in series you cannot.

As I already said, if the lights aren't on, there will be no current anyway. It just doesn't matter here. Drop it.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



bstruss
Novice

Dec 21, 2014, 6:29 PM

Post #7 of 17 (1483 views)
Re: Trailer run lights? Sign In

I guess my meter is lying to me then when I measure amperage when I hit my brake lights and have the the lead connected from the open vehicle plug to ground (in series) - and same with the turn signal. Okay, I will drop it and ask elsewhere as you aren;t following.


(This post was edited by bstruss on Dec 21, 2014, 6:34 PM)


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 21, 2014, 6:34 PM

Post #8 of 17 (1479 views)
Re: Trailer run lights? Sign In

You're going to have to because you are just to stubborn to listen to people that know more about this than you. I will tell you one more time that current has absolutely no bearing in resolving this problem. It only measures the amount of electricity being consumed and if the lights don't work, they aren't consuming anything. If you want to be stubborn and not listen, then you can try another forum but don't be surprised if you are told the same thing.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



bstruss
Novice

Dec 21, 2014, 8:04 PM

Post #9 of 17 (1469 views)
Re: Trailer run lights? Sign In

I do understand your point that current is correctly measured in line with a load. However, my point was that in the presence of proper voltage at the right points at the run light socket, I simply did a quick isolated current measurement to ground (and compared it to other light functions which registered amperage). Sorry if I was confusing in my post.

In the absence of having another vehicle to power the trailer independent of the current vehicle/trailer wiring, is there a recommendation on how to do so otherwise?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 22, 2014, 3:05 AM

Post #10 of 17 (1457 views)
Re: Trailer run lights? Sign In

As I already stated, use a Power Probe or an independent power source to power and ground the trailer plug directly to find out if your problem is in the trailer or the truck and then we can proceed from there.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



bstruss
Novice

Dec 22, 2014, 6:40 AM

Post #11 of 17 (1449 views)
Re: Trailer run lights? Sign In

You only said to power the trailer, and did not mention how. Thanks for your insulting and impatient attitude. BTW, it ended up being a badly damaged wire which gave me a voltage reading but would not support current - as I suspected. And you might have suggested that all along instead of ad hominem.


(This post was edited by bstruss on Dec 22, 2014, 6:48 AM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 22, 2014, 7:32 AM

Post #12 of 17 (1447 views)
Re: Trailer run lights? Sign In

Happy Holidays sport. Keep in mind all here are volunteering their time for free with some pretty impressive experience.


Trailers are their own thing and have had many myself mostly for boats. Dunk those in water and expect a new one to behave for long just doesn't happen. Others tilt, get left sitting for months and the plug of any style gets ignored.


The suggestions were on target by my view. Alternate power for example. Take a whole battery or jumper box and test out trailer from it without the vehicle at all is what I take that as and have done just that.


Glad it's fixed for you. If trailer wiring is over your head I mean no harm but get help with that too. In fact you mentioned U-Haul by name and locally they are quite well equipped to provide parts and know how to test out assorted trailers they rent and have to if in that biz.


Info from people can be all over the place at a site like this and hard to know what the person can or can't do or understand.


Have a nice day,


Tom



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 22, 2014, 7:40 AM

Post #13 of 17 (1442 views)
Re: Trailer run lights? Sign In

Next time you can tell a different forum how much you don't know.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Double J
Veteran / Moderator
Double J profile image

Dec 22, 2014, 4:56 PM

Post #14 of 17 (1432 views)
Re: Trailer run lights? Sign In

At least we all know what ' ad hominem.' means now....


Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Dec 22, 2014, 5:14 PM

Post #15 of 17 (1428 views)
Re: Trailer run lights? Sign In


Quote
At least we all know what ' ad hominem.' means now....


and here I thought it was some type of oatmeal.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.

(This post was edited by Discretesignals on Dec 22, 2014, 5:15 PM)


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 22, 2014, 5:18 PM

Post #16 of 17 (1424 views)
Re: Trailer run lights? Sign In

ad hominem [ad hom-uh-nuh m -nem, ahd‐]
  • Word Origin
adjective 1. appealing to one's prejudices, emotions, or special interests rather than to one's intellect or reason. 2. attacking an opponent's character rather than answering his argument.



Yep, he's just a stiubborn dumbass



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Double J
Veteran / Moderator
Double J profile image

Dec 22, 2014, 7:18 PM

Post #17 of 17 (1421 views)
Re: Trailer run lights? Sign In

Maybe that's what Ralph Kramden was saying all this time.....Homina,homina,homina






  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap