Replaced the Battery and now Problems

[chriscowles]

Originally Posted by dnicoll

But, if the battery was connected reverse polarity - wouldn’t the reverse polarity fuses blow? Typically (I think?) two fuses in the fuse panel and a battery installed reverse polarity would take out both fuses? In which case nothing would work.

The reverse polarity fuses probably would blow but the slide motor is wired directly to the battery. Not having a 5th wheel I don't have landing
gear but my electric tongue jack is also wired directly to the battery.

Those circuits are protected against overload by a Type I circuit breaker at the junction box under the frame of the trailer. It's not affected by the direction of current flow.

I cannot explain why the lights would remain on. Maybe that has something to do with current flowing backwards through a neutral line, bypassing a fuse? Dunno.

[ependydad]

Originally Posted by dnicoll

But, if the battery was connected reverse polarity - wouldn’t the reverse polarity fuses blow? Typically (I think?) two fuses in the fuse panel and a battery installed reverse polarity would take out both fuses? In which case nothing would work.

I wondered the same thing, but here's what I came up with:

Aren't those fuses just output from the converter? The converter won't charge the battery any longer, but the 12v system would still work from the battery.

I know in my fifth wheels, there are bus bars that come directly off of the positive side of the battery that have a bunch of things connected to them.

[Grumpy7159]

Reversed polarity may explain the electric jacks and slides operating in reverse, but the lights on all the time confuses me. A complete circuit is required to light up the trailer. If the switch is in the lighting circuit it should turn off the lights (open the circuit). Something is back feeding your system and it could be an electrical component in your equipment. If the battery is indeed connected properly, I would start removing loads from the DC circuit until your systems operate properly. I usually disconnect the battery bank and feed the trailer with a battery charger. Easier to disconnect when trouble shooting if needed. Good luck.

[campers302]

Sure hope we get a reply from the OP. Cant wait to see the answer to this one.

[Diesel Thumper]

Based on what you said, 12v internal lights work properly but slides and landing gear works backwards.

I'm assuming you're hooked up to 120v shore power and therefore you have power to the converter. The reason the internal lights work is because the 12v power is coming directly from the converter not the battery. The reason the slides and landing gear are not working correctly is because they get there 12v power directly form the batteries. Your batteries are connected in reverse. Reverse the battery cables and everything will work correctly.