Electrical connectors and inline fuse

The 12V system does not work with our battery in our 2001 Coleman folding trailer. The lights/heater etc.. work fine when plugged into the 110 receptacle of our generator, but we get no power when running off the battery. We have hooked it up to brand new batteries and still nothing. We took it to an RV service center and they informed us that our converter was bad. They replaced it and I brought it home only to discover that the problem had not been fixed. Now I am furious with them, and with myself for not checking the repair before I drove 110 miles home. So, now I'm going to try and resolve this on my own. I have confirmed that power is not making it to the fuses with a tester. I am going to replace the wiring and components that lead from battery to the point where the wiring disappears inside the hollow tubing of the frame of the trailer.
Here are my questions: 1) there is an inline fuse attached to the positive wire called a "short stop". Does anyone have any suggestions on a type of inline fuse to install on the new wire, and where can I order it? 2) At the point where the wires go into the frame of the trailer the wires are connected to one another by some sort of clip connector. I've been dragging around the section of wiring that has the male connector on it to autopart stores and various places asking if anyone has a connector that I can use as a replacement. I'm getting blank stares. Is there some sort of connector I can use and where do I get it? Or should I just splice the new wires and old wire that is going into the frame together? That would be a new adventure all by itself....
Thanks for any help and advice.

If you had 12v power when plugged into110, then your converter was working fine. I'd stay away form that shop in the future - they obviously know nothing about diagnosis or RV electrical systems.

Shortstop is a brand of 12v circuit breaker. Any brand of 12v breaker would do and auto parts stores should have them, but here is a source for that brand:
http://www.burnstines.com/power/circuit-breakers/shortstop-mini-breakers

"some sort of clip connector" could be one of dozens of connectors that snap together. The Molex brand is popular in the RV world, but only one of many such. Can you post a picture?

But if you are replacing both halves of the connector, it doesn't make any difference what the style is. Just get another that has enough amp carrying capacity and the right number of wires. A Grainger store might be a good place to ask, but you need to know the wire size (gauge) and required amp rating.

As Gary said, the "Short Stop" device is a circuit breaker, they come in two types, on one you have to push a button to reset it, the other resets itself after a period of time.. Look it over for a button and if you find one.. Push, HARD.

I am assuming you have battery voltge on one side and (unless you are plugged in) nothing on the other, should be same voltage both sides.

As to what kind of "inline fuse" to install.. I'd recommend a brand new in-line breaker just like the Short Stop.. Need not be the same brand but should be the same size.

Thanks for your replies. I have replaced the ring terminals, wiring, 30 amp fuse and connectors on the section of wiring I menitoned above. Still no 12 V power. Used a multi-tester at the battery and the end of the new wiring I assembled - 12.7 V at each. There is a point where the wiring emerges at the end of the trailer and a Molex connector. At that point the voltage is .965 and I don't know if that is a significant finding or not. If I ever figure this out, I'll come back and post my findings.
Thanks for your responses.

It sure sounds like you have an open circuit or the possibility of a bad ground.

Molex connectors are highly suspect or so I'm told.  Check both sides of that connector.

I'd like to thank everyone for their ideas and advice. It turns out that the ground wire was intact at the point where it connected to the camper, but there was an open circuit somewhere in the wiring. I ran a wire from where the old ground connected to the frame and attached it to the negative terminal of the battery. The 12 volt system now works perfectly.
I learned quite a bit from this little adventure - thanks again.

Glad to hear that the problem is solved and you are ready to go RVing.

I love stories like this one.  One person learns something, others smile in helping, problem fixed,...

The way a RV story should end.