No Battery Power Due to Surprise CB

[trailerm]

Just adding this here in case someone else runs into this. I got a 1995 HiLo trailer in the fall and have been working on some issues it has. This one relates to everything working fine when plugged in but when it's unplugged there is no power at all. Replaced the battery with a new one and still didn't work. Also with the new battery I could get the top to go up and down when plugged in instead of having to jump it with my truck.

The problem was that there was a circuit breaker by the fuses under the dinnette seat. My trailer had both resettable CBs in the battery/hydralic lift compartment and both of those were fine. I replaced the CB in the dinnette with a new one and now the battery power works. That CB was a resettable one but I didn't see the switch since it was located practically under the fuse box. None of the wiring diagrams I found on this excellent forum showed a CB at that spot.

Adding some pictures to show where it is.

 

[JackandJanet]

I wonder if this was a CB that was added by a prior owner? Can you determine what it protects? However, great job finding the problem and an excellent post documenting what you found. Like you, I don't recall anyone ever mentioning a CB in this location.

Welcome to the forum - we're delighted to have you with us!

- Jack

 

[trailerm]

Thanks this forum is a great place for info and help. As for the CB, it may have been added by a prior owner - I was thinking it was an original one since it matched the ones in the battery compartment. From what I can see, one side is the red wire from the battery compartment, which already has a CB, and then on the other side it has two wires. One goes to the fuse box and the other goes to the converter.

Next up - resealing the roof! With any luck I should have our trailer ready to use in the spring

 

[JackandJanet]

OK, you might already know this, but the wire going to the converter, is actually a charging wire FROM the converter TO the battery. The one going to the fuse box is the 12V battery feed to all the interior 12V devices, such as lights, the water pump, fans, etc. Both are being routed through the CB and it doesn't matter that the current flows in opposite directions. But, the way the wires are connected, the converter CAN supply power to the fuse box if plugged into shore power, even if the CB is popped, which is why things worked when you were plugged in.

It looks to me like a prior owner DID add the CB, which is interesting, because in my trailer, with the Elixer converter, there are 2-30A inline fuses BEHIND the fuse panel (sort of hidden) that are on the charging line to the battery. Why there are two, I don't know. I DO know that if both of them are blown, I still get battery power to the fuse box, but if at least one of them has blown, there is no converter charge to the battery.

I would think you could bypass the CB on the battery to fuse box line, since the fuses will protect against any overload there. This would at least give you battery power if there's an overload between the converter and the battery that causes the CB to trip.

I have a thread about "Converter Troubleshooting", where I conclude that having the trailer plugged into shore power when raising the top or even when using the electric tongue lift can put such a heavy load on the battery that it might blow one or both of my inline 30A fuses (or your C. As an aside, it's also been noted that putting a heavy load on the battery when hooked to your tow vehicle's charging line can blow the 30A fuse in the tow vehicle for that line (which I've done at least twice).

Now, I make sure the trailer is not hooked to any external power when I raise the top or use the tongue lift.

I wonder if the prior owner replaced the 2-30A fuses with the CB to make restoring converter charging easier than replacing the fuses? Not a bad idea, since getting to those fuses is a bit of a pain.

- Jack

 

[Trblandy]

Seeing those pictures and Jack reviewing his valuable knowledge reminds me to have a good look at my circuit breakers and converter again. I did find one of those gray blocks with bolt posts in the storage drawer when I purchased the 2203T in 2019. I’ll see the trailer in March and let you know what I find.
Tom

 

[JackandJanet]

Tr, I'm a bit like you - we just had about three feet of snow and I won't be doing anything with my trailer until it melts and things warm up a bit.

I've decided to investigate the possibility of replacing those two dratted fuses with a 30A CB that I can get to easily if needed. I'll have to trace the fuse wiring to make sure they are not protecting something else, however.

- Jack

 

[Rolff]

As I read this I thought "I wonder if he knows of that manual breaker hidden behind the fuse panel?" It doesn't even look like a breaker does it? It took me hours to find mine it was in the manual showing it in the battery box but they relocated it inside. It might be a 1995 only issue. Once I knew there was one I looked until I found it. I hit it with some red spray paint so I would not forget.
Do you have a manual for yours I have a PDF copy.