1999 Burro Electrical Question

[BobTheBurro]

Hey folks!
This is my first post and we have found a lot of useful tips here. THANKS!
My family and I bought a used 1999 17' wide body Burro. We are in the process of bringing it up to speed and figuring out all the systems. Our first major issue is diagnosing the electrical. I will try to communicate what I know and have tried.

I plugged the burro's exterior electrical A/C into a 20 amp plug via an extension cord off the house. With the breakers switched ON we get power to all the interior/exterior outlets and the ceiling fan powers up. After being plugged in for a long period of time (8 hours) the interior/exterior cabin lights and the exhaust fan/light still did not power up. Without knowing the condition of the deep cycle battery, I took the battery to AutoZone and they determined it was DEAD. With the ANSWER in hand I hooked up the new-fully charged battery and got nothing. Now I'm getting stumped. I checked all the GFCI outlets and they seemed functional. Then checked out the glass fuses and they seemed normal. I then unplugged the exterior power and noticed the fan was still running. Hmmm. So I checked the GFCI outlets and they worked as well. Obviously the battery was powering those items but still no power to the "D/C" lights and range hood. Again, stumped, I went out side and plugged back in the house power and heard a click (Burro Windows Open) from the Breaker box. Everything cycled down for a second and came back up. - Assuming it switched to A/C. Went back into the burro switched on a cabin light and it worked. YAY! All the lights were on and the exhaust fan and lights were functioning. AGAIN, went outside and unplugged the house power and heard another click, everything powered down for a second and came back on. And again, back on battery power. I was so relieved but still stumped on why it was now functioning. At this point I was just excited that things were on and assumed it would stay that way.

Next Chapter...
A couple days go by with full function. Still plugged into house power, I used the lights and moved onto other projects. After finishing each day, I would flip off the breakers and unplug the power (not sure if that is needed).
The next day, I am working with all lights on and with no noise or notice the cabin lights power off but the fan stays on. Confused, I flip the breakers, unplug and plug back in and still only the outlets and fan work. Back to square one. So, I assume the battery was not charging the whole time and I drained the battery. So, I borrowed an A/C powered Battery Charger from a friend and hooked up the battery. It charged for awhile and automatically shut off. Assuming I'd hook it up and be back in business, I reconnected the battery and I can not get the cabin lights on at all. That is where it sits now. I called an electrician buddy of mine, he is confused by it but also does not know much about the whole AC/DC conversion etc.
If anyone has any thoughts, ideas, etc. I would be so grateful. THANKS for reading and look forward to some suggestions.
Best,
Andrew
Owner of Bob the Burro.

[Borrego Dave]

Welcome to FGRV Andrew, that was a very good first post. You'll be getting the answers soon .

[Joe MacDonald]

sounds like you have a switch over relay between the DC side and the AC side that is not working, can you get a brand/model number of your converter?
It also sounds like you have an inverter if your AC outlets stayed powered when you unplugged shore power. These will kill a battery quick, even if you have no load, just powering the inverter.Pictures of your electrical equipment would be a help also
Joe

[BobTheBurro]

Maybe these can help! Thanks Joe, I'd love to see if these shed some light.
Best

[Joe MacDonald]

Definitely a switch over relay, the round doohickey to the right of the breakers, the main panel you took pictures of is your AC/DC distribution centre, the converter is probably behind it, looking at the panel it is similar to mine. The converter could probably use an upgrade as it may not have a smart charger. Do you have pictures of the light fixtures?

[Joe MacDonald]

The relay may switch the DC loads between the converter and the batteries, can you get a !
Model number from the converter

[BobTheBurro]

Joe,
Thanks for all the info. Here is the latest...
On a whim, I purchased a new "round doohickey" (See Attached) and installed it. It makes the same noises and has the same functionality but still no cabin lights.

Also, Noticed when the unit switches between AC/DC the roof fan changes directions. That seems odd too.

I tried to get more model info but the back of the unit is tricky to get into- or at least I'm not totally sure how.
Again, Thanks for all the help.

[Joe MacDonald]

OK, your response just gave a huge clue, if the fan changed direction you have a polarity problem, the fan should never change direction switching from shore to battery. Could mean you have reverse charged your battery as well. Remember, in an rv or trailer black is positive, white is negative. Get a cheap multi meter, and check polarities coming out of the converter, and t the battery
Joe

[John in Michigan]

To add to Joe's post, MAKE SURE the wire from the doohickey (switch) to the battery is attached to positive (+) terminal on the battery.

EDIT: Looking at your fourth photo in post #4, a thick black wire is attached to the doohickey (switch); also, a thick white wire is attached to the common bus bar. Are those wires coming from the battery? If so, the black wire should be attached to the battery positive (+) post and the white wire should be attached to the battery negative (-) post.

[Joe MacDonald]

on my converter the relay is not present, I have a manual switch that does the same thing, if there is a polarity problem, you may have popped a fuse somewhere
Joe