I had a problem in the fall with my battery terminals corroding. After some homework here, I figured I was probably overcharging the battery leaving it plugged in too often at home......I cleaned the terminals and all was well. About 2 months ago, I noticed the electric tongue jack running slowly and the terminals were a little corroded so I cleaned them up. The last 2 months I have taken a few overnight trips. I took one 2 weeks ago with no problems. When I got home, I left the TH hooked up to my truck(including the electrical connection) until yesterday. 2 nights ago, I plugged into 110v so I could turn the fridge on, and when we went out to load it yesterday morning, the carbon monoxide detector was signaling low voltage......so, I cranked up the generator fopr a few minutes and that went away. We went to out park, the tongue jack was very sluggish so I figured I knew what that meant.....We ran the stereo for 3 or 4 hours......The Th was plugged into 30 amp all night. This morning, the tongue jack was still super slow......I just got home and opened the battery box and the terminals look pretty clean......So, here are the questions.....
Isnt the converter supposed to charge the battery when it is plugged into a shoreline???/
Isnt the battery supposed to charge off of the tow vehicle????
Could the programmer in my truck have drained the battery in the camper while it sat???? (i doubt that)
I just hooked up a charger and the battery is basically dead......it is a one year old TH......
As far as I know( and I may be wrong) the tongue jack and stereo work directly off of the battery, but I would have though it would charge when plugged into the 30 amp.......
Have you checked the water level in the battery?
Fill to just cover the plates then charge. When fully charged (24 hrs) top off to just below (1/4") the split ring that extends down into the cell. Use distilled water only.
Converters do charge the battery but many will cause excessive water use especially in warm (90+) temps. If you post the converter make and model you will get better info.
2001 F150 SuperCrew 5.4 Lariat Offroad 4x4 Tow Package 4.10 Truetrac
2006 Keystone Springdale 249FWBHLS
12K SuperGlide, KGE3000Ti 2.3kw rated 2.6kw max
Frank's voltage booster, Prosine 1800 powered by 4 GC2 batteries
Spray you btry post with NAPA Chain Lube. Works great for me. JMO
RET Army , DW Donna , Summer (Furkid) . Class A, 2000 Gulf Stream, DIRECTV, YAMAHA 2400 GEN , TOW 97 Wrangler. Garmin GPS 2720 . "Living Our Dream". NASCAR FAN (20,18,11,29,31) Love CO & NM
I've had similar issues myself and suspect the charging ability of the converter.
Had a situation just this past weekend. I was dry camping and since it was hot and humid, ran the generator all day Saturday for the A/C thinking it would recharge the batteries. Shut it off at night (the 12volt draw was minimal - no furnace, no lights, no fans) and by Sunday morning the 2-12volt batteries would only light one light on the charge level indicator. Sometimes, I have inadvertantly left an outside light on and run it down. The step light is easy to miss, and I installed an indicator light inside to remind me it's on.
Previously, even on shorepower or generator, if the 12volt demands were high (CD player, spot lights, interior lights, furnace, fans) I connected an automotive battery charger to the batteries, and had no problems. If not, it seems the batteries can draw down faster than the converter can recharge them.
This is my next project. A couple of 6-volt batteries, and diagnose the charging issues. Hooking up the Auto charger works well, but kind of a PIA that I don't want to deal with every time.
My batteries are 3 years old and don't hold a charge as well as they used to.
When I measure the voltage and the specific gravity with a hydrometer I get a substantial difference.
I am in the process of running a desulfate charge and an equalizing charge to see if things improve.
I do not keep my trailer plugged in to shore power and do not keep a float charge on the batteries. I charge them when I get back from a tip and then disconnect until the next trip. Normally we camp once a month. But from November to February we do not use the trailer. This usage pattern is not good for batteries.
Wayne in San Jose
TV1:2002 Chevy 1500HD 4wd Crew Cab,Valley Odyssey brake ctlr,McKesh mirrors
TV2:2008 GMC 2500HD long bed 4wd Crew Cab,GMC brake ctlr,GMC mirrors
TT:Trailmanor 2720
Honda 2000
Yamaha WR250R,Polaris Sportsman 700 X2,Polaris Scrambler 500
On my trailer the battery disconnect switch must be on or they won't charge, either from shore power or the vehicle while driving or from the generator. If the stereo and the tongue jack are wired directly to the battery, is it possible that the disconnect switch is off and the batteries aren't getting charged?
Fred
2006 Attitude 26FSAK
1997 F-350 Powerstroke
1993 KTM LC4-400
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9 year old son
9 year old daughter
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, Summer (Furkid) 
. Class A, 2000 Gulf Stream, DIRECTV, YAMAHA 2400 GEN 
, TOW 97 Wrangler. Garmin GPS 2720 
