A Plea for Help- Trailer Lights

[aaron42ash]

Is there anyone in spokane that could help me out? I am trying to get out this weekend and they aren't friggin working again. I just got a new converter kit installed on my truck at uhaul, and installed brand new lights on the trailer. The trailer lights work because when i plug them straight into a battery with an extra truck end flat four they light up. great...right? no. As soon as I connect the flat four on my rig. boom the lights don't work. The little lights that test a circuit on the truck side flat four also stop lighting up, but all my truck brake lights work. It's just making me insane because I'm pretty good with this stuff. Sorry if none of this makes sense, but if you can help let me know. I'm going to try to get it back to uhaul and bring the light kit with me to show them what's up.

[The Quadfather]

Is there anyone in spokane that could help me out? I am trying to get out this weekend and they aren't friggin working again. I just got a new converter kit installed on my truck at uhaul, and installed brand new lights on the trailer. The trailer lights work because when i plug them straight into a battery with an extra truck end flat four they light up. great...right? no. As soon as I connect the flat four on my rig. boom the lights don't work. The little lights that test a circuit on the truck side flat four also stop lighting up, but all my truck brake lights work. It's just making me insane because I'm pretty good with this stuff. Sorry if none of this makes sense, but if you can help let me know. I'm going to try to get it back to uhaul and bring the light kit with me to show them what's up.

Hard to know exactly what you have without seeing it.... but in a flash, consider:

http://www.harborfreight.com/12-volt-ma ... -8847.html" onclick="window.open(this.href);return false;

This is simple stuff. Magnet attachment for quick short trip to close lake. Single wiring harness to what I assume U-Haul installed on your vehicle. I can say though that I no longer will do wiring harness for trailer via U-Haul. Those idiots have wired it wrong twice on my cars. Caused me a short, that almost left me stuck 10 miles up a dirt road on a mountain. I go to the dealer for even a wiring harness.

[Steve Ericsson]

Also, check your hitch to receiver connection, make sure that it isn't too rusty or if your hitch is new, scrape the powder coating/paint off where it contacts the receiver. With a flat four plug, your ground is established through your hitch in most cases. Flat four you have left turn, right turn, tail and brake but no ground through the connector. Had this issue a few times with new hitches or rusty hitches that wouldn't make good contact anymore.

[MarkFromSea]

Also, check your hitch to receiver connection, make sure that it isn't too rusty or if your hitch is new, scrape the powder coating/paint off where it contacts the receiver. With a flat four plug, your ground is established through your hitch in most cases. Flat four you have left turn, right turn, tail and brake but no ground through the connector. Had this issue a few times with new hitches or rusty hitches that wouldn't make good contact anymore.

I disagree with what you have written above. Flat four has ground, running, left and right. Both left and right are energized for brake.

[dutchman2858]

Also, check your hitch to receiver connection, make sure that it isn't too rusty or if your hitch is new, scrape the powder coating/paint off where it contacts the receiver. With a flat four plug, your ground is established through your hitch in most cases. Flat four you have left turn, right turn, tail and brake but no ground through the connector. Had this issue a few times with new hitches or rusty hitches that wouldn't make good contact anymore.

I disagree with what you have written above. Flat four has ground, running, left and right. Both left and right are energized for brake.

Don't know about this for sure, but seem to recall some similar "ground thru ball" on a rig of mine in the past. Easy to check on a trailer where lights work fine: disconnect ball, but leave trailer lights plugged to tow rig...do they still work?? Discussion resolved...

[hewesfisher]

Also, check your hitch to receiver connection, make sure that it isn't too rusty or if your hitch is new, scrape the powder coating/paint off where it contacts the receiver. With a flat four plug, your ground is established through your hitch in most cases. Flat four you have left turn, right turn, tail and brake but no ground through the connector. Had this issue a few times with new hitches or rusty hitches that wouldn't make good contact anymore.

I disagree with what you have written above. Flat four has ground, running, left and right. Both left and right are energized for brake.

^^^^^ This is correct, that's why there are 4 wires. If all the wires are properly connected with a flat 4 connector, one of them is a ground. Don't rely on the ball to trailer, or receiver to truck for you ground as it's very unreliable.

The problem is he is not getting any signal from the converter installed by U-Haul.

The little lights that test a circuit on the truck side flat four also stop lighting up, but all my truck brake lights work.

There's nothing wrong with your trailer lights. Take your tow vehicle back to U-Haul and make them correct the install, it's what you paid for, so have them do the job right.

[MarkFromSea]

Gotcha, I've never used one of those converters.... I didn't know what the "little" lights were. LEDs I suspect.

When he said they went out when plugged in, I suspected a short of sorts in the towing vehicles tow harness... conflicts with the trailer.... that's assuming trailer is correctly wired.

If I'm recalling this correctly, it's your odd prong out of the four that is ground... I agree, back to uhaul!

[MotoBoat]

Is there anyone in spokane that could help me out? I am trying to get out this weekend and they aren't friggin working again. I just got a new converter kit installed on my truck at uhaul, and installed brand new lights on the trailer. The trailer lights work because when i plug them straight into a battery with an extra truck end flat four they light up. great...right? no. As soon as I connect the flat four on my rig. boom the lights don't work. "The little lights that test a circuit on the truck side flat four also stop lighting up, but all my truck brake lights work". It's just making me insane because I'm pretty good with this stuff. Sorry if none of this makes sense, but if you can help let me know. I'm going to try to get it back to uhaul and bring the light kit with me to show them what's up.

In the Bold, highlighted, italicized sentence above. You have isolated the problem. As stated by Hewes, MFS, and possibly others, what work was completed by U-haul was not done correctly. The lights on the trailer work fine, the truck lights work fine. The flat four plug on the truck is dead. The wire connection between the trucks rear lights and trailer side of the 4 prong plug is the problem, as discovered with your test light. Sounds like a power wire from the truck might be attached to the wrong flat four connector wire. Perhaps what U-haul did, resulted in a faulty connection of two wires, and that wire was the power wire.

Work backwards from the trucks four connector. Does the power wire from the truck that feeds the flat four plug connector, test to have power? Not at the plug, but stab through the sheathing in the wire to test for power (to the tow plug). Do all colored truck wires attach to matching four plug wires at the truck? If the trucks "hot" leed tests okay, and is connected to the matching colored flat four plug wire. Make certain the flat four wires correspond in the proper order. Seems I have come across a wire in a flat four connector that did not match the trucks wire color coating. That is as far as I would go to rectify the problem.

My guess, based on whats been said by the original poster. Is that the power wire is the focus of attention. With power to the flat four plug, something should light up on the trailer, even in the wrong order. Unless the power wire is attached to the ground wire, which would show as a blown breaker.

If non of the above solves the problem, might try another U-haul in your area. In hopes of finding a sharper employee.

Not being familiar with a "inverter" or the installation. Read on the net, how one is installed. Pretty basic, inverter installed via Velcro or screwed through a bracket,into place. One wire to ground and one wire to power side of battery. That's it.

Did U-haul do any other wiring?

[hewesfisher]

If I'm recalling this correctly, it's your odd prong out of the four that is ground... I agree, back to uhaul!

Correct.

[gfakkema]

...

[aaron42ash]

Thanks for all of your posts. I have taken it in to uhaul 2x since the original install and I still cant get them working. I will just bite the bullet and take them into a shop. I have looked around and it doesn't seem like there are many choices for shops that do installs. Do most boat shops?

[Big D]

Thanks for all of your posts. I have taken it in to uhaul 2x since the original install and I still cant get them working. I will just bite the bullet and take them into a shop. I have looked around and it doesn't seem like there are many choices for shops that do installs. Do most boat shops?

I had my pick up and boat wired up at an RV dealership and have never had an issue. I think it cost me around $50.00

[ridgeratt]

So by the term " Converter". Does this mean you have a electric trailer brake control installed? Most of the rigs today have a wiring package already in them. If you add a plug to the bumper it is a simple plug and play pigtail. So if you did have the brake package installed it sounds like perhaps they got the wires juggled. I would check the plug at the rear bumper first to see if it is correct with out the trailer hooked up. You can look at the cover and some times they have the pin out marked on it or just do a search and you can find the pin out. Run it with a test light.

[Amx]

http://www.etrailer.com/fitguidet1.htm" onclick="window.open(this.href);return false;

install vids;

http://www.etrailer.com/tv.aspx?productgroup=Wiring" onclick="window.open(this.href);return false;

at bottom;

http://www.etrailer.com/Electrical" onclick="window.open(this.href);return false;

http://www.etrailer.com/dept-pg-Wiring- ... l_Fit.aspx" onclick="window.open(this.href);return false;

converter system like one of these?

http://www.etrailer.com/dept-pg-Wiring- ... l_Fit.aspx" onclick="window.open(this.href);return false;

[ridgeratt]

I have re read the post.
If the plug on the back of your vehicle isn't working with a test light. Check and see if there isn't a set of fuses that control the back plug. If the lights on the rig work. In the owners manual look for the fuse block diagram.

[MotoBoat]

I have re read the post.
If the plug on the back of your vehicle isn't working with a test light. Check and see if there isn't a set of fuses that control the back plug. If the lights on the rig work. In the owners manual look for the fuse block diagram.

Good id-er wright there! Plus, the limited reading I've done online involving converter installs. Indicates the power wire of the converter, commonly has a inline fuse. Check for that as well.

[aaron42ash]

Guys, thanks so much for your help. Without it, I wouldn't have been walleye fishing today. It turns out that the trailer lights had bad grounds at the lights and on the truck end, but not the flat 4 on the boat end. Cleaned them up and installed new insulated grounds at the lights and at the hitch and bueno they work great. Thanks again for everyone's help. I must admit I think I tried ALL of the suggestions before finding that small problem. Take care

[MotoBoat]

Guys, thanks so much for your help. Without it, I wouldn't have been walleye fishing today. It turns out that the trailer lights had bad grounds at the lights and on the truck end, but not the flat 4 on the boat end. Cleaned them up and installed new insulated grounds at the lights and at the hitch and bueno they work great. Thanks again for everyone's help. I must admit I think I tried ALL of the suggestions before finding that small problem. Take care

Glad you persisted and fingered out the issue. I must admit, my experience with a bad ground, usually shows itself as a delay in the trailer light blinking just after the truck light. So, in other words, with a good ground both trailer and truck lights should blink at the same time, without delay. Bad ground, trailer tail light flash is delayed (slower) from the trucks blinker.

This would have been something U-haul did incorrectly?

[aaron42ash]

On the truck side, yes. They had grounded the truck side to the frame of the vehicle instead of the hitch, and that caused the problem on that end. Only took 3 trips down to haul to figure that one out =/

[hewesfisher]

This would have been something U-haul did incorrectly?

Yep. Failure to provide a proper ground for the trailer lights is simple, basic electrical work. All of this could have been prevented if U-Haul had done a proper install in the first place. A proper install means what they've done actually works the way it's supposed to before taking money and sending the customer home.

aaron42ash - Glad to hear you got the wiring problem solved and were able to go fishing!!!