What does the battery actually do?

[Toni Arnold]

Ok, this is such a stupid question I should know but here goes......
The battery that is on the front of the trailer tongue, what is it's purpose?
I'm thinking it only works the jack.

I dry camp at the beach for a couple of days at a time, so I have portable lanterns for light inside and have a couple of lithium battery chargers for my phone. Am I missing out on utilizing the battery? Could it be powering my lights inside the trailer?

Thanks!
Toni

 

[Raycfe]

If you trailer has electric brakes a battery will provide emergency power to the brakes incase the trailer breaks away from the tow vehicle.
If you have an electric tongue jack and or electric roof lift it will power them
If you have an electric water pump and or furnace it will power them
A battery will power the ceiling lights or anything else that runs in 12 volt DC.
A battery will have to charged by something. Many campers will have power center with a built in battery charger when plugged into Shore Power. Also if the tow vehicle has a wired "charge line" that could also charge the battery when connected.
A power center "convertor" will also power every thing the battery does except the brakes.
A bare bones trailer would not need a battery.

 

[A-Ranger12]

Should power the inside lights and vent fan. If there's a 12v accessory outlet, it can charge a phone with a 12v phone charger. Just make sure to plug in the camper for a day before heading out to charge it.

 

[rsdata]

First and foremost that battery is a necessary safety item to power the electric brakes should the trailer break-away from the tow vehicle IF, the break-away cable from the trailer to the tow vehicle is properly installed when hitching. This is a legal requirement for trailers usually anything larger than 1500# which your trailer is.

You probably have an electric water pump to pump water from a filled water tank to the sink and the shower. Sounds like you do not fill the tank nor use the water in the sink or shower, so no worries there.

The interior lights in the camper are ALWAYS powered by 12 volts, either from the battery, or from a converter ( 110 VAC to 12 VDC) when the trailer is plugged into a 110 VAC plug commonly called using Shore Power. The act of plugging in your trailer to 110 VAC will power the jack, the interior lights, pump and maybe a radio? if you have one AND recharge the trailer battery all without using battery power. When plugged into Shore Power you may also have a microwave oven, roof top air conditioner and TV set which will also work, as they REQUIRE 110 VAC to work and will NOT work with 12 VDC battery power only. SOMETIMES RV TV sets do work with 12 VDC, but that is not common.

Have you checked the liquid level in the battery by popping off the two tops off the battery? The liquid level should reach to the lower part of the split ring looking inside each of the 6 holes in the battery. Refill with DISTILLED water ONLY if the liquid level is low. The battery may be shot. You could tell if the interior lights of the trailer do NOT light when disconnected from your tow vehicle, then the battery either needs a charge or could just need replacing.

Give us a few more details to help you further.

 

[Toni Arnold]

Thanks for your replies. Yes, it has electric brakes and the break-away cable is installed correctly.
I'm still somewhat confused. The battery is fairly new (purchased in May 2020) It's a marine battery from Costco (looks like a car battery). I have plugged into Shore Power one time at a campground and everything worked, I just prefer being at the beach which has no hookups. I tote my own drinking water and campground does have restrooms & showers.

Does the battery charge when I'm plugged into the 7 way pin while towing or do I need to plug in like you said from home a day or two before? If I disconnect the 7 way pin once there, the interior lights should work, correct?
I would just like to use my interior lights and be able to charge my phone. Such a waste if I'm not utilizing the battery because of ignorance.

 

[Anthony Hitchings]

Do not expect your car/SUV etc to charge the battery properly if at all. Try it and find out.

 

[WrkrBee]

Does the battery charge when I'm plugged into the 7 way pin while towing or do I need to plug in like you said from home a day or two before? If I disconnect the 7 way pin once there, the interior lights should work, correct?

Check the battery voltage. Then plug the camper in and start the tow vehicle. If the voltage increases, the tow vehicle is trying to charge the camper battery. With a charged battery, and the tow vehicle disconnected, the interior lights should work.

 

[Susan Premo]

Do not expect your car/SUV etc to charge the battery properly if at all. Try it and find out.

Mine does. 2012 aliner. Sounds quite the same.

Thanks for your replies. Yes, it has electric brakes and the break-away cable is installed correctly.
I'm still somewhat confused. The battery is fairly new (purchased in May 2020) It's a marine battery from Costco (looks like a car battery). I have plugged into Shore Power one time at a campground and everything worked, I just prefer being at the beach which has no hookups. I tote my own drinking water and campground does have restrooms & showers.

Does the battery charge when I'm plugged into the 7 way pin while towing or do I need to plug in like you said from home a day or two before? If I disconnect the 7 way pin once there, the interior lights should work, correct?
I would just like to use my interior lights and be able to charge my phone. Such a waste if I'm not utilizing the battery because of ignorance.

Not a stupid question, I have a lot of questions.

 

[jeepster04]

The vehicle wont really charge the battery, but it will keep it from going dead if you have the fridge set to DC, etc.

Reason it wont charge the battery, the voltage drops too low by the time it gets back to the battery. Battery needs higher volts to actually charge. The more amps it pulls, the lower the volts will be at the 7 pin since the wiring is so small.

Curious, have you tried turning the lights on in the camper when not on Shore Power?

 

[Sjm9911]

In other works , pulg it in for a few days before your trip. Try it at home fisrt, after charging the battery it should work the lights. If it dosen't, get back to us here. You need to charge the battery every so often as the gas detector is always on. So it will eventually drain the battery to nothing.

 

[WrkrBee]

You need to charge the battery every so often as the gas detector is always on. So it will eventually drain the battery to nothing.

Disconnect the battery when stored. This keeps the battery charged longer. When we purchased our camper, the battery was <4 volts when plugged in. She had never disconnected the battery in three years.

 

[Sjm9911]

Yes , when not in use for a while, keep it on a maintainer or disconect it

 

[nhlakes]

You've received lots of good advice here, but the simplest thing to do, assuming you have the camper stored in the driveway, may be to just plug it in for a couple of days, then un-plug it and see what works.

The small amount of charge from your minivan would not be enough to restore the battery of it were very low. It's more of a 'trickle' charge.

Trailers are designed so that most of the stuff works on 12v (the battery). As mentioned, your AC and microwave will not work, but everything else might. If you put water in your tank you might find that your shower, bathroom, sink, water heater, refrigerator, heater, stereo, TV, etc., all work.

Suggest you also read the manual for your trailer (if you do not have it you can likely find it on line) and then keep asking questions here. Pictures help!

 

[zak99b5]

Oh and don't try to run the fridge on battery power--it'll be flat in short order.

 

[Toni Arnold]

Thanks everyone, I appreciate it.
The trailer is in my driveway so it's easy to plug in for a couple of days to check it. I have never tried the lights while disconnected, I just assumed they wouldn't work unless plugged into Shore Power. Duh. I'll do that and see if the interior lights work and report back. Then, I'll disconnect the battery until my next trip.

I don't use the fridge, I bring coolers for food and drink which is fine because it's only me. My last trip was the first week in November. I try to go once a month but California campgrounds are closed at the moment so I've had two cancelations so far. I don't know how to check the voltage on the battery and I haven't been able to find a manual for my TT.

I don't use the water tanks (need a better tow vehicle than the Odyssey) so I don't have to worry about the water pump/heater.

 

[rsdata]

Then, I'll disconnect the battery until my next trip.

I don't know how to check the voltage on the battery and I haven't been able to find a manual for my TT.

As was mentioned above... IF you store the trailer and do NOT disconnect the battery the battery will within a week or so discharge to the point that it will be ruined. CO detectors are always ON and possibly radios and other items in the trailer will drain the battery when parked and not being actively charged all the time from Shore Power or a battery maintainer ( about $30) hooked directly to the battery.

Please pick up a less then $10 voltage test meter ( VOM) from Harbor Freight Tools or any hardware store or Walmart... any cheap meter will do. You can easily check voltage of a battery using the red and black leads from the tester to the POS+ and NEG- terminals of the battery. It is not even necessary to get RED to + and BLACK to -... just hold the pointed ends of the probes onto the metal terminals with the meter set to DC VOLTS, 20 Volt or greater range.

A fully charged battery from Costco or anywhere should be 12.6 or more volts. If your battery measures less than 10 Volts then it will be permanently damaged, losing capacity to hold a charge. It may charge, but will not be as good as new ever again.

Chances are your battery is already damaged if you have left it hooked up for days/weeks without charging the battery. You will never know without purchasing a cheap meter to measure the battery voltage. Watch youtube videos to learn how to use the meter.

AND... there is NO SPECIFIC manual for nearly ANY trailer or RV, just generic manuals for maybe the stove, microwave, etc. Again, search youtube videos for specific info on trailers in general... there are hundreds of videos on there to sift through, OR ask specific questions here or on Forest River RV forums.

 

[rsdata]

MORE...

you mentioned earlier that you are pretty self-sufficient with lighting and such at the beach without hookups.

Perhaps you really do not need much of a 12V trailer battery, never using water pumps or trailer lights... only using the electric jack.

If the current battery is not good, then just purchase a smaller tractor starter battery from somewhere like Tractor Supply. These $40 batteries will be good enough to power the emergency break-away brakes and meet legal requirements, plus the electric tongue jack when necessary.

Just a thought before spending another $90 on an RV/Marine battery from Costco.

 

[Toni Arnold]

MORE...

you mentioned earlier that you are pretty self-sufficient with lighting and such at the beach without hookups.

Perhaps you really do not need much of a 12V trailer battery, never using water pumps or trailer lights... only using the electric jack.

If the current battery is not good, then just purchase a smaller tractor starter battery from somewhere like Tractor Supply. These $40 batteries will be good enough to power the emergency break-away brakes and meet legal requirements, plus the electric tongue jack when necessary.

Just a thought before spending another $90 on an RV/Marine battery from Costco.

Thank you for all of that info. Sounds like because I haven't been out for 2 months, my battery is shot. I'll get the meter and check it out.

 

[Susan Premo]

Mine does. 2012 aliner. Sounds quite the same.

Not a stupid question, I have a lot of questions.

It's a 2011, not 2012.

 

[Jimbow]

Thanks everyone, I appreciate it.
The trailer is in my driveway so it's easy to plug in for a couple of days to check it. I have never tried the lights while disconnected, I just assumed they wouldn't work unless plugged into Shore Power. Duh. I'll do that and see if the interior lights work and report back. Then, I'll disconnect the battery until my next trip.

I don't use the fridge, I bring coolers for food and drink which is fine because it's only me. My last trip was the first week in November. I try to go once a month but California campgrounds are closed at the moment so I've had two cancelations so far. I don't know how to check the voltage on the battery and I haven't been able to find a manual for my TT.

I don't use the water tanks (need a better tow vehicle than the Odyssey) so I don't have to worry about the water pump/heater.

One option is filling near your final destination. I usually only travel with a few gallons for flushing and washing.