Bad battery

[Sandybar]

Help, I think I destroyed my battery. bought new trailer and new to RV scene. I noticed battery was dead after several inactive days of use. My bad left a light switch main on. Went to charge battery with charger and hooked leads up backwards. After realizing what I did I checked fuses, good, and then hooked up charger correctly. now I don't think it will hold a charge. Did I destroy my battery?

[oldmanAZ]

Why do you believe your battery won't hold a charge?

I'd suggest you disconnect the battery cables from the trailer and then try charging the battery. Check the voltage across the battery as it charges.

Do you have specs on the battery charger output amperage? Your battery is probably seriously discharged and will take a while to recharge.

There are reverse current fuses in the converter that will blow if you connect the trailer's battery reversed. I haven't heard anyone report that it happened when they connected a battery charger reversed.

[Sandybar]

I charged for 12 hours yesterday and charger never fully charged only about 50%. Went out this morning and charger maxed out 12 amps to start charging again said battery was 0% charged. Now after charging for 2 hours it is at 25% charged.

[norty1]

Take it to a auto store and have them do a load test on it.

If it's toast, you can chalk it up as a expensive lesson.

I would verify the reverse battery fuses in the converter are good.

[klpoppe]

Like said before, disconnect the battery from the camper and let it charge fully. Letting it run down all the way could kill the battery but unlikely if you only did it once. Check the water level in the batteries. You could still have something on that is causing a draw ( LP and CO detector as well as radio are parasitic draws). Hooking a charger up with reverse polarity should not be a big deal as modern chargers have reverse polarity protection built in. Once you get this figured out invest $30 in a battery disconnect switch and turn it off when trailer not in use.


If it is still doing it take battery to an auto parts store and have them load test it.


Good luck...

[Sandybar]

I disconnected it and will continue charging. If I can't get a full charge I will get it load tested.

Thanks