Main Trailer Fuse

JohnG4706 wrote:
I have a Puma 23FB TT. I use a 30 Amp cord to hook my TT upto. Recently I shorted the umbilical card between my SUV and my TT. CW found the problem and when they replaced the Main Trailer Fuse under the front end, just back from the battery, they replaced it with a "Tow Ready 40 Amp Circuit Breaker." They gave me the package the circuit breaker came in and the blown fuse they removed.

I'm without power again. I just hooked up a Battery Tender solar panel to keep my battery charged while in storage. Having the package I went and bought a 40 Amp fuse at Advance Auto Parts.

Here's my question: On the side of the original blown fuse shows "12V X41 50A". On the side of the new fuse shows "12V X30 40A". Was the original main fuse a 50 Amp fuse? Could CW replacing it with a 40 Amp Circuit Breaker be my current problem in that it should be a 50 Amp Circuit Breaker?

I'm confused. Thanks.

You appear to have FUZES confused with CIRCUIT BREAKERS. If the one CW originally replaced physically looks like the one they installed you never had fuzes only circuit breakers. In fact I would be extremely surprised if any trailer would use an actual fuze for what you are describing, but stranger things have happened. What AFAIK that is normally used is a self resetting CB which should not normally need to be replaced unless it tests bad.

Yes the original appears to have been 50A so CW replaced it with an undersized replacement HOWEVER ....

1. A 40A should be plenty and even a 30A would probably work.

2. CW and now you should not need to replace those and there are two types either self resetting or manual reset both of which don't have to be replaced if tripped just like a normal CB. I would recommend using the self resetting type which IIRC are the ones normally found at both RV and Auto Parts stores.

Larry