Charging question Jayco Flight SLX newbee

rwinestock · 08-08-2019, 03:11 PM

Had for 2 months. Hardly used the dual batteries except for light on one week trip. Should have been recharged on 250 mile return home. Showed down to 1/3 charge on tester over stove. CO alarm has now gone off for two weeks. Do have trickle solar tender hook-up. No charging source to battery except 30 AMP from house. With all breakers off, 30 AMP hookup for 2 days to attempt to recharge battery. Still CO alarm. Checked batteries today. 6.7v and 7.1v respectively. These are both DEAD from the factory. Is this common? Scheduled appt. next week to fix.

RetiredOne · 08-08-2019, 03:34 PM

They are definitely toast at those voltages, usually anything under 11 volts means they are DOA.

Some chargers need to see "some" voltage from the battery before they turn on. With the voltage levels that low, the charger might not turn on.. I don't know what you have..

Or, maybe the charger isn't working, so even when you were plugged in before, it wasn't charging the system. It's going to take some detective work to figure out what's going on.

oldmanAZ · 08-08-2019, 03:38 PM

Welcome to the forum.

A few questions come to mind...
- You've owned the trailer for 2 months?
- During that time, did you have the trailer plugged into shore power or disconnect the batteries from the trailer?
- You have dual batteries: Are they both 12volt batteries or both 6volt?

And a few facts...
- The CO alarm will go off due to low battery power.
- The 12v power from your tow vehicle has too little current flow to charge batteries while driving.
- Plugged into shore power, with all breakers off, the converter will be off and will not charge your batteries.
- IMO, the built-in battery meter is not a good indicator of your battery condition. An inexpensive digital voltmeter is a good tool to help sort out many electrical issues.
- The dealer probably didn't install dead batteries, but dealers often do not disconnect the batteries after installing them. The draws on the battery from the CO detector, radio, etc. will drain the batteries.

rwinestock · 08-09-2019, 04:36 PM

Thank you. At one point I did have breakers on with shore power. Dual 12v Batteries did not respond. I did not disconnect the batteries from the trailer at any point. Do the 12v batteries only charge with shore power? Do they also charge when stationary, but truck still hooked up electrically? Everything worked at the dealer and on the first trip out, but started having light issues early on.

ALJO · 08-09-2019, 06:56 PM

You have to be on shore-power for charging the batteries from the converter. Disconnect the battery terminals and check if there is 13.6 volt on the terminals.

Hooked up to the TV with running engine should also charge your batteries (check your 12 Volt + in the 7 prong outlet on your Tow Vehicle).

rwinestock · 08-09-2019, 09:04 PM

Tomorrow I will remove the cables and check the charge for 13.6v on both batteries. I will also run the tester on the 7 prong connector at the truck. Should be good as it ran all the lights, but maybe that amount of voltage is not needed to do that. Why would the TV need to be hooked up? I do have a TV installed, but what is the significance of that running? Thank you.

RetiredOne · 08-09-2019, 10:31 PM

TV stands for Tow Vehicle... I know, at first I thought it was the same thing you thought...

I didn't want to watch television either..

So when he said hooked up to the TV (tow vehicle), that was to see if the 13.6 was coming though the 7 prong outlet from the engine running. This provides some voltage to the trailer, but many have said, not enough to fully charge the batteries, due to the size of the wires.

You can also put your meter on the battery terminals and see what voltage passes to the batteries when the TV engine is running. Then turn off the TV, and plug into shore power and you should see over 13 volts at the battery terminals, if the charger is kicking on.

rwinestock · 08-10-2019, 02:02 PM

Thanks. That clears it up. Tow Vehicle. I've been hooked to shore for a day and a half again. Still at around 7v.

rwinestock · 08-10-2019, 02:03 PM

Great advice on isolating the charger too.

rwinestock · 08-10-2019, 02:22 PM

Did the following per advice above: 1. The Shore power at 30A/125 socket is 119.76.
2. When I hooked the trailer electrical to the TV, both batteries read 12.6v almost immediately. 3. Conversely, when I unhooked the truck and went strictly to shore power, the volt meter read 9.6v on each battery within a very short time. Is it the inverter that's not working?

rwinestock · 08-10-2019, 02:23 PM

The shore power checked with AC. The batteries DC on the meter.

RetiredOne · 08-10-2019, 08:16 PM

Did you turn all the breakers back on in the converter after plugging into shore power? Did you see higher voltage on the batteries after that, just like you saw when plugging into the TV?

If, with all the breakers on plugged into shore power, and you don't see the jump in voltage, looks like it's the converter/charger not doing it's job. Or possibly a broken wire or connection that feed the 12 volt to the battery.

SB_James · 08-11-2019, 06:42 AM

Quote:

Originally Posted by rwinestock

Did the following per advice above: 1. The Shore power at 30A/125 socket is 119.76.
2. When I hooked the trailer electrical to the TV, both batteries read 12.6v almost immediately. 3. Conversely, when I unhooked the truck and went strictly to shore power, the volt meter read 9.6v on each battery within a very short time. Is it the inverter that's not working?

Your batteries are dead. When connected to the truck you are reading the DC Volts from the truck. The battery Volts should never go below 12 V to keep them healthy. Below 11 V means they’re not coming back. Your converter probably has an under volt protection circuit for safety. You should never force a charge on a dead battery.

Unfortunately your first task is to buy new batteries and then go through your system to figure out if anything is wrong. If you store your trailer for long stretches you should disconnect the batteries at the terminals or install a disconnect switch close to the terminal to kill the parasitic draw on them.

Good luck.

rwinestock · 08-11-2019, 01:16 PM

Forgot to turn the breakers back on. Will do that now and measure voltage after a bit. Will report back.

rwinestock · 08-11-2019, 01:19 PM

This is under warranty. My appointment with the dealer is Tuesday. This happened less than a month after purchase. In addition, had a solar-powered tender to keep batteries primed. But, yes, I get what you're saying about why I got the better read on the trailer batteries once I hooked up the TV (because it was now reading the TV battery strength, not the trailer batteries independent of that).

rwinestock · 08-11-2019, 04:01 PM

After an hour or so, connected to shore power with all breakers on, no TV power, the trailer reads 12.92v and 12.93v for both batteries.

Then, I disconnected the shore power, with zero draw from inside the trailer cab, waited one hour, and rechecked the isolated trailer battery voltages (again, no TV power). They were, 11.6v each.

BTW...the whole three weeks time, my Carbon Monoxide alarm continued to beep. If I reset it it will back off sometimes for a bit before resuming its annoying sound. Thankfully, we live on some property where it won't be heard easily.

SB_James · 08-11-2019, 04:34 PM

So it sounds like your converter is charging the batteries, but they are no longer servicable. Fully charged 12V batteries should be at 12.8 to 12.9 V open circuit (assuming these converters have a conservative charge Voltage of 2.15 V per cell.)

When you were connected to shore power and measured the batteries, you were measuring the float charge voltage of the converter. Once you disconnected the rig and measured the batteries by themselves, they measured well below 12V.

Hopefully these steps you've taken can help the service tech figure out if the problem was in the batteries or if you have another issue going on.

By the way, I use https://batteryuniversity.com as a reference for all things related to batteries. It's a great resource.

RetiredOne · 08-11-2019, 04:50 PM

Well, there's some good news and some bad news. The good news, once you turned on the breakers, it shows that your converter/charger is working and not the issue.

The bad news, the batteries won't hold a charge, and need to be replaced. When you told us they were in the 6 to 7 volt range, that's a dead battery that won't hold a charge.

The alarm going off was because of low voltage, once it goes below 11, it will sound.

So, best guess, put in some new batteries, keep the breakers turned on, and when plugged into shore power, your batteries will charge.

Just remember.... NEVER let them go below 12.0 volts, and ALWAYS top them off when not sure.

rwinestock · 08-11-2019, 07:29 PM

Thank you and I'll make a note of that. These batteries were on my new trailer fresh from the dealer about a month out. They should not have been bad. Pretty sure that's it and your help is appreciated--all of you. With no load several hours later tested after removing from the shore power, the voltage tested at 11.55v each. And the CO alarm did not go off (I'm guessing because the batteries didn't go below 11v this time). But, this is the first time it even stayed up that high in weeks (again accounting for the Carbon Monoxide alarm tripping off those weeks.). I'm only worried now that what I thought was a constant problem has become an intermittent one. Could just be a bad cell. In any case, I'm wanting new batteries.

RetiredOne · 08-11-2019, 08:36 PM

It could be bad batteries from the get-go. Wouldn't be the first time dead batteries were delivered with a new unit. Many times the dealers forget, and let the batteries die while the rig sits in the lot. Go back and demand new batteries.

On my rig, the chassis battery wouldn't hold a charge when I picked it up. But I know that the chassis sit at Ford, then they are shipped to Jayco and sit there during the modifications. Then the rig gets shipped to the dealer, and sits some more.

So, I ended up having to get a new battery for my chassis, which was 6 months old.... age means nothing to these batteries, if they let them discharge a few times.... they're dead.

My coach battery was weak too, but I'm watching it to see how it reacts.

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