Strange Electrical Issues

[Epitome]

Hi everyone,
My wife and I bought a 2008 R-Vision (TLX-189QB) 19' trailer last year. Due to circumstances, we didn't get to use it last season, but we're heading out soon for a much needed getaway. I'm trying to get everything ready to go, but we've encountered some strange electrical issues that I'm hoping to get some help with, please.

Shore power doesn't seem to be getting to the charging system, or the converter is hooped. I first noticed that our batteries (two 6v deep-cycle, near-new and water topped up) weren't charging when the trailer was plugged in to the house. I had to charge them using a 12V smart charger, and even then, that charger ran at 15v overnight and was still going when I checked this morning. Multimeter says they're over 12v and I'll check them again tonight.

Yesterday I checked the two 30A fuses at the panel which run the converter, and they were good. Then I read online that typical trailer wiring at the batteries is black=positive and white=negative. Mine was reversed, so I swapped them and promptly blew the two 30A fuses at the panel. I have put it back the other way and replaced the fuses. But when I'm plugged in to shore power and use my multimeter (set at 12v DC) to check the main battery leads on the trailer, I get either nothing or the needle goes backwards. Any ideas on what the heck is happening? Is something wired backwards and causing an issue? I'm at my wits end here.

If we can't fix this before we leave, we're considering taking the 12v battery charger and running that off our generator to recharge the batteries. We also have a 100w solar panel that might help, weather permitting. Is that feasible? Thanks in advance for your help!

[Boomerweps]

Before you change the circuit breaker, check to see if it is receiving 12VDC from the converter and that the other wire reads the same as the battery. If so, bad breaker OR it needs reset. They have a small pinhole that you press a pen or hanger wire in to reset, like the reset on a home router.
I found it odd also that key electrical components are so exposed on my TT frame front crossmember, like having your truck battery terminals in the wheel wells.

[enblethen]

I would try to locate and get size(amperage of ciruit breaker. If unable to get size get a 30 ampere.

[Epitome]

Thanks so much, everyone. You've been a huge help! I'm going to grab one of those replacement breakers that opnspaces mentioned and replace the one we have while we're out at the site. But at least we can go without being overly worried.

[pianotuna]

By all means go on the trip and take along the battery charger. Peace of mind is quite worth while.

[opnspaces]

Yes it's possible. Those circuit breakers are not sealed very well. The Amperage should be marked on the breaker itself. You can pick up a new breaker for about $10 at almost any auto parts store.

[opnspaces]

With shore power off take a voltage reading at the reverse polarity fuses to ground. You should get battery voltage. (11.5v in your case)

Then plug in shore power and check again at the fuses. Hopefully you get 13.6 v or higher. If the check still shows battery voltage (11.5v in your case) then yes your charger is probably hooped. In that case just run for the weekend like you suggested with the shore power plugged in and if needed add in a standalone battery charger as well.

[Epitome]

@opnspaces
Yes, we have a little box just like that underneath the trailer not far from the batteries. The contacts look pretty rusted. Tried to attach a pic from Google Drive, but it's not working. Is it possible that the corroded terminals are causing the voltage drop to the batteries? I find it strange that such an important part of the electrical system is left open to the elements like that. Yes, your diagram of series wiring is what I've done. Thanks so much for your suggestions so far.

[opnspaces]

Verify that your 6 volt batteries are wired in series (right side picture below.

[Epitome]

Batteries are wired correctly. I have one cable going from pos-to-neg between the two batteries, then the trailer leads go to their respective posts (in my case, backwards from usual). I did some more digging. When I tested the leads, I was trying them the way they're supposed to be wired, but mine are backwards. Apparently, if you use the multimeter backwards, it'll go backwards. Go figure. So I've gone back out and tested the leads again, but in 'reverse'. I'm only getting about 11.5 volts from them, so I think there's still an issue. But at least I don't think there's a major one any more. If we do what we normally do, and run both the shore power cable and the 12v charger from the generator, that should be ok, right? Please tell me if you disagree. Then we'll get it checked out by someone when we get back from our trip.

[opnspaces]

As evidenced above you can't just go by wire color as mine is the opposite. My Jayco from the factory is wired Black positive and white negative.

If you have no power after replacing the fuses that blew in the trailer you possibly have a second fuse or circuit breaker out on the positive wire on the tongue that's blown.

At the battery take a moment and just look at the wires and where they go. The negative(s) is going to go to the frame and probably fairly close to the battery. The positive(s) will usually have a fuse or a small box (circuit breaker) inline near the battery.

A circuit breaker is typically (not always) a small box with two bolts and nuts with a wire under each nut. Using your meter set to 20V DC check from each post on the circuit breaker or each window on any fuses back to the negative terminal on the battery. It has to be the post that the negative wire from the trailer is connected to.

You should get the same voltage measuring from each post or window back to the negative post on the battery. If you get 12v on one post or window and zero or a significantly smaller reading on the other post or window you have a bad circuit breaker or blown fuse.

[enblethen]

Fuses that blew are reverse polarity. Rih was wired correctly. I would verify that the batteries are wired correctly. Possible they are not wired is series.
Connect back up as were originally connected. Then pug in the rig. Verify voltage at the batteries for converter voltage of around 14 volts. Not present check converter voltage. If converter is outputting 14 plus volts.
Does the batteries charge when connected to TV?
Correct color coding for 12-volt DC is red for positive and black for negative. Yes, some are not wired that way. Would be a good idea to start marking red positive and black negative.