trailers lights not working on Scamp

[krboren]

I have no power to my trailer lights. They had been working fine until recently. I have tried: 1. Fuse on tow vehicle (good) 2. Another tow vehicle just to be sure (no luck). 3. Fuses under front bunk (one was bad...at least one of the side lights on cabinet is now working...but no trailer lights) 4. Replaced 4 prong connection on Scamp (still no power). 5. I bought a circuit tester but I'm m unsure how to use it. I'm ready to fly the white flag of surrender but it was suggested by a fellow fiberglass Rv member thati should try posting here. Thank you all...

[Donna D.]

Hi Kristin, glad you found us! Someone will be along shortly to help... I believe in leaving everything electrical to the experts

[mcbrew]

If no lights are working, it is almost certainly a ground problem. There is usually a white wire that screws onto the trailer frame. Check the connection -- it is easily broken. If you are not familiar with vehicle electrics, the chassis (frame) acts as your connection to the negative side of the battery. All of the other wires are positive going to the lights.

Typical "flat four" wiring is as follows:

White = ground
Yellow = left turn/brake
Green = right turn/brake
Brown = tail lights (all marker lights)

The way to use your tester would be to work backwards from the tow vehicle and see where you aren't getting juice any more. Start at the flat four in the TV and see if the male connector (white wire) has continuity to ground. The next connector should be the brown wire, and should be hot whenever the TV lights are on. The other two will flash with turn signals and brakes.

If you aren't getting ANY signal from the flat four of the TV, then a fuse is burned out or your lighting converter is fried.

If you have a good ground and good signals on the other three when appropriate, then move on to the trailer itself. Again, if you have no lights, your ground is the most likely culprit.

[krboren]

Thank you for your response. There is a white wire that appears to be rivet attached to the fiberglass side. It is located under the front buck a few feet from the entrance point of the tow wires into the Rv. Is this the ground?

[Carol H]

Kristin, your profile doesn't show what year your Scamp is but on mine there are also fuses inside the converter box (which is under the rear bench in mine) - you may want to take a look at that - I have to unscrew the box to get at mine.

[mcbrew]

Originally Posted by krboren

Thank you for your response. There is a white wire that appears to be rivet attached to the fiberglass side. It is located under the front buck a few feet from the entrance point of the tow wires into the Rv. Is this the ground?

You've got it! Now, you want to make sure that is a good connection to the frame of the trailer. Some folks forget about the frame and run a dedicated ground back to each light. I haven't found that to be necessary, but it works. Remember, wires can be broken inside of the insulation. I had a cargo trailer with no lights, and it turned out that the ground was broken just being the flat four connector. It looked fine, but if I wiggled it just right, the lights would flicker on.

[john warren]

it takes a little time , and thinking but you can figure this out.
start at the fuses of course.
then the ground. these two fix a whole bunch or problems.
then test to see if you have power coming into the fuses.
and check the light bulbs. are they good, do they have power coming to them? are contact rusted? there isn;t much else on these things.

a good resource for you is "the 12 volt bible" you can get a copy at your local library.

[Carol H]

Kristin if you do not already have one there is in the documents section here an electrical diagram for the Scamp which may also help you. If you cant find it let us know and will post it here for you.

[krboren]

Thank you everyone for your help. I'm back at work and it's dark when I return home so the troubleshooting on the trailer will have to wait till the weekend. Carol...I have seen the electrical diagram on the scamp owners manual. I know Donna D. also started a very helpful document section in this forum for us to access. Thank you for the post. John...I will check out the 12 volt bible. My goal is to become educated and I need a lot of help with all things electrical. I used to think that plumbing was the source of the most frustration in home repair but I'm starting to think electrical comes in a close second! Mcbrew...the ground appears to be riveted to the frame. Would I need to slice the wire and reground it? The day the lights stopped working, I had stuffed a sleeping bag into the underbunk storage compartment...it was a tight fit. Maybe I wiggled the wire loose by that action. Thanks everyone for helping get me on the road again. I'm tired of "camping" in the side yard of my house...although the bed is cozy and the dogs don't seem to now the difference! (yes...I often sleep in the camper even with a warm king sized bed inside...we Scamp owners are passionate about our campers!)

[Carol H]

Originally Posted by krboren

Would I need to slice the wire and reground it? The day the lights stopped working, I had stuffed a sleeping bag into the underbunk storage compartment...it was a tight fit. Maybe I wiggled the wire loose by that action.

LOL - I would suggest not slice anything until you figure out by using a meter what power is working and what does not. You indicated that one light is working is it the kitchen 110 one?

Yes you could have wiggled something loose as the whole wiring system from the tow harness and battery goes through the front of the trailer into that hatch under the front bunk on the passenger side. You may want to open up the rat fur a bit more on the front wall of the hatch to see if any of the connections in that area came loose.

[john warren]

lets see if i can draw a basic 12 volt diagram.

this is where your battery is
^ lightbulb
+-------fuse------------------@-----...--------ground to
frame
_ -------to frame

as you can see the positive side of you battery passes threw a fuse,
then to you bulb, from there a groung wire passes to you frame for ground.
this takes it back to where you battery is grounded by the negitive post.
so if you walk threw it one step at a time there isn't many places you can go wrong.
now having said that, i have been known to simply throw up my hands and take it to a mechanic.

[john warren]

grrrrr, my label for the lightbulb moved when i posted,,,,,
@= lightbulb

[Carol H]

LOL John I seem to recall that your trailer is fairly new to you - wait until you cut open the rat fur at the front of the trailer inside the hatch just to see the connections stuffed behind it and the type of connections used. Perhaps Scamp has changed its connection method on newer Scamps but on older one like mine they used basic twist caps and I know from searching for the cause of a lighting issue I had that some are not all that secure. Pretty easy if one over stuffs the front bench to wiggle something out of its connection behind the rat fur. Personally wish Scamp used shrink connectors in that area at least.

[Maarestad]

Originally Posted by krboren

I have no power to my trailer lights. They had been working fine until recently. I have tried: 1. Fuse on tow vehicle (good) 2. Another tow vehicle just to be sure (no luck). 3. Fuses under front bunk (one was bad...at least one of the side lights on cabinet is now working...but no trailer lights) 4. Replaced 4 prong connection on Scamp (still no power). 5. I bought a circuit tester but I'm m unsure how to use it. I'm ready to fly the white flag of surrender but it was suggested by a fellow fiberglass Rv member thati should try posting here. Thank you all...

One good way to check what's up, is to slide back the trailer connector and hook up the negative cable of a 12 volt battery charger to the white wire, and touch the red, green, and brown wires one at a time, with the positive wire of the charger, while someone calls out the good results on the trailer lights!

[frankcfx]

They make fuses with a lite that glows when the fuse is blown. Great for checking fuses, they are more expensive but save a lot of time when you are checking fuses!!