Crazy Electrical Problem

[joeg11781]

So this weekend we were camping, and my battery was dead. No problem, I just borrowed my uncle's (at his suggestion of course) in order to use my tongue jack to hook the trailer up to the truck. His camper was working perfectly. After i put the battery back, none of his 12v stuff works (slideout, lights, etc...). He found both his 30A fuses in the panel (on the 12v section) blown. So we went to replace and as soon as he put it in, it sparked and blew. We then unplugged from 120AC and same thing happened, Flipped all breakers off, same thing happened.
So whether he is plugged in or not, nothing running off 12v works. and as soon as he goes to replace either of those fuses, they spark (pretty badly) and blow. We then tried all of the above again but disconnected battery cable until fuses were in, then put cable back on, and blew the fuse immediately.

I'm assuming since it still did it when not plugged into shore power, I can assume its not the converter? We checked to make sure the batter cables were hooked up right and the ground was solid, other than that, can't really tell too much about where the wires run.

I feel like crap since this is obviously related to me taking that battery, so if anyone could give some help, I'd really appreciate it.

 

[Grandview Trailer Sa]

Re: Crazy Electrical Problem

Those fuses protect the trailer from the battery being wired backwards. You have wires reversed on the battery.

 

[joeg11781]

Re: Crazy Electrical Problem

That's exactly what I thought Grandview, especially because when he was bringing his slideout in, just prior to the fuse blowing, he said the switch was working backwards (the "out" direction was bringing the slideout in) so i figured the cables were reversed causing the motor to spin the wrong way maybe, so we checked the cables well and they were right, but is there something that may have flipped everything that may necessitate the cables to be purposely switched from now on? I don't even know if that's possible, electrical isn't really my forte

 

[Grandview Trailer Sa]

Re: Crazy Electrical Problem

I don't see how that is possible, we have had trailers delivered and the switches work backwards...the drivers put the cables on reversed. Only when we plug it in does it blow the charging fuses. I would look again.

 

[joeg11781]

Re: Crazy Electrical Problem

I think your probably onto it, over the weekend, I also tore up the plastic gear set on my slide out motor when i tried to bring it in, the gears were so messed up i couldn't believe it went from working fine friday to that much of a mess on sunday. (granted, when trying to bring it in, we probably held the switch longer than we should have when we heard the gears gridning but saw nothing moving) but I'm wondering now if the polarity in the CG hookup was reversed, being that my uncle's slideout switch operated backwards and the fuses meant to protect against rev.pol. blew consistently., and maybe mine was the same and i ground those gears by holding the "in" button but the motor was trying to go out further. I might have to check that out. I know some seasonal people at the CG, might call them and have them check

Thanks for the help Grandview

 

[TexasClodhopper]

Re: Crazy Electrical Problem

Hey, Joe, no offense meant, but you are ignoring the simple solution. The most obvious one.

You took the battery off by disconnecting the wires.

You put the wires back on the battery backwards. (Probably because you set the battery back into the box backwards or your battery has those wingnuts holding the wires on.)

It's just that simple.

Get a $20 voltmeter and check the batteries for the correct polarity if you can't see the "+" and "-" signs molded into the battery, and if you can't tell that one post is larger in diameter than the other. The "-" is grounded to the frame somewhere.

 

[C Nash]

Re: Crazy Electrical Problem

I have to agree wit Ken and Tex. It all started when the batt was replaced so it has to be hooked up wrong. Are ther any wires other than the pos and neg big wires? Maybe a small white or black. The white can be grnd on TT. Time for some serious looking and If you are not ok with electrical might be best to take it to a good tech. Could be cheaper in long run. Reversing pos and neg can do a lot of damage on newer rvs. Good luck