What did I fry?

My husband and I own a 2008 Bighorn 3670RL. He is working overseas and I recently replaced the batteries. I don't know much about anything mechanical, so I asked a friend about hooking up the 2 12-volt batteries... either positive to positive or positive to negative. Well, apparently, he told me wrong. He had me hook them up in a series instead of parallel and I got a spark. a BIG one. Well... I figured out that was wrong, so I hooked them up the other way, parallel and now my slides work, but I don't have power to anything in the trailer with just the batteries. The lights work when plugged in, so I am assuming I did not mess up the converter, but is there a fuse or something between the batteries and the converter that I could have messed up? I checked the breakers and the fuse box, and all seems ok. I haven't located the converter, but from other posts, I am assuming it is in my basement, behind the wall. I just was wondering if someone could tell me possibly what I should look for. Thanks for any help. With the time difference between Texas and Guam, it is hard for my husband to talk me through stuff and I don't remember us ever needing to know where the converter was. Thanks for any help.

Welcome to the forum Debbiebundick. This is a great place to share information. Hopefully you will get some help here.
There is a row of breakers behind your battery, one of em, below the hydraulic pump. Some are auto reset an some are manual reset. Remove the red covers and feel on the side for a tiny reset button.
You may also have blown a fuse or two on your converter. You are right, it is located behind the wall in the basement. If you have never had the wall down, there are a couple of screws located in the UDC that hold part of the off door side in place. There is a maze of wires and water lines back there.
I know for sure there are at least three fuses on it. Don't know if there are any more.
That should give you a place to start.

Peace
Dave

Debbie,
This is easy. You have tripped the 12V DC circuit breaker that sits between your batter and the 12V fuse panel in your coach. Push the reset button and all will be well. The breakers are on the wall behind your battery. Here's a picture to help identify them.

View attachment 17453

Welcome to the forum Debbie, if this is how you describe a problem not knowing much about anything I'd love to see a decription of a problem you know something about. GOOD JOB.

As for finding your converter (it's good to know where it is), it's probably on top of the black tank, against the bulkhead at the rear of the basement area...after you pull the wall down. Most likely, it will be on the opposite from the UDC, meaning you will need to remove the basement panel on the curb side of the basement. It will also be buried under a maze of wires, next to the framing for the bedroom steps.In this version of Basement of Doom, if you look towards the rear wall on the left side, you can see part of a gray box. That's where your converter most likely is. I've moved mine to a more accessible location.


View attachment 17455

Debbie,

Since you replaced the batteries and are a little fuzzy on the wiring of them, you likely cross-polarized the lines for a brief moment. The converter is protected against cross-pol by those 3 (30 amp blade style) fuses others mentioned.

If your new batteries are both 12 volt type, then you wire them in parallel as positive to positive and negative to negative. If they are 6 volt type, then you wire them in series to obtain 12 volts as positive of one battery to negative to the other battery, then the coach wiring goes to the other open positive and negatives on those batteries.

From the coach is usually a red and a white wire. The red wire is the positive and the white is the negative.

IMPORTANT: Confirm the battery wiring BEFORE you change the fuses in the converter. Otherwise you'll blow the fuses again. Also, consider purchasing at least 6 of the 30 amp ATO style blade fuses so you have spares. Finally, as a precaution, unplug the converter from the wall outlet that it plugs into, before you change the fuses. This will ensure there is no load on the converter as you replace the fuses one at a time.

I apologize for this level of detail, but it's important stuff to know and this is a real easy thing to do. If you changed the batteries, you CAN find the converter and change the fuses. Members of this forum will walk you through it. If you'd rather speak to one of us by phone to go through this, just click on our usernames and send us a PM or email with your phone number. I am sure anyone here would be happy to speak to you by phone to walk you through this.

Jim

PS: Here's what the converter looks like:

codycarver said:

Welcome to the forum Debbie, if this is how you describe a problem not knowing much about anything I'd love to see a decription of a problem you know something about. GOOD JOB.

Click to expand...

I was thinking the very same thing, my wife would never even attempt this project. GREAT JOB!!!

I'll just confirm what most are saying. Believe it or not... don't ask me how... I crossed the polarity on batteries on my coach yesterday. Yep, both 35 amp fuses on the converter fried. Two new fuses and things are back to normal. Note to self... don't rush when installing the battery just because it's 23 degress out.