Help, no 12V

[Bobbie54]

Everything was fine. Yesterday at home I plugged in and plugged in a heater to warm the trailer, and cool the fridge. Today I unplugged and we drove about 4 hrs total (including ferry sitting time.) Got to site (boondock) and no 12V at all. When I first tried the fridge had lights that said check (gas was off until I got here so that made sense.) Tried turning it off and on and it won't come back on. Nor will any of the lights. Pump was left on and originally had a light but that died, too.

So what to check? There is no way the 12V switch got touched; it is under a seat and under other stuff. Nothing that could mess with it. I pulled a couple of fuses (Blue) and it is possible the 12V one isn't solid, can't tell, nothing was blinking. Batteries look fine and should be. I used the trailer 3 weeks ago, yesterday was rainy but we were plugged in, and there was sun before that, plus they should be charging while I drive . Looks like everything is off.

And I can't get the fuses back in until I'm ready to dismantle the bench/front dinette so I want a plan.

 

[Perry Butler]

Batteries look fine and should be.

Need more than "look fine". What's your voltage at the batteries with no charge?

We had that happen once and found our 5.0's absorption fridge was running on 12v and would have depleted the batteries if I hadn't decided to look at my Victron's bluetooth shunt, finding the batteries less than 12.5v.

Terry claimed it wasn't her that hit the 12v button, but it certainly couldn't have been me.

Food for thought,

Perry

 

[Bobbie54]

I have not checked voltage at the batteries- no idea how to do that with them connected- but my voltmeter inside doesn't even register. How do I measure voltage across two connected batteries?

I did pull the dinette seat off where I thought the switch would be. No switch. But behind the foam piece of insulation something is glowing yellow. See pic.

 

[Centex]

EDIT - sorry, I was slowly typing while above posts were made.

To check voltage on the pair of batteries while connected just put your meter probes on the negative post of the battery with the ground cable and the positive post of the battery with the power-out cable - that'll at least give you the voltage of the pair (your voltage of interest to start).

End EDIT
_________________________

Everything was fine. Yesterday at home I plugged in and plugged in a heater to warm the trailer, and cool the fridge. Today I unplugged and we drove about 4 hrs total (including ferry sitting time.) Got to site (boondock) and no 12V at all. When I first tried the fridge had lights that said check (gas was off until I got here so that made sense.) Tried turning it off and on and it won't come back on. Nor will any of the lights. Pump was left on and originally had a light but that died, too.......

Is there any chance that in this sequence of events your (3-way?) fridge was running in 12 volt mode for the 4 hours of the trip after you unplugged from home shore power and had propane off? If so, that might have left you with near-dead batteries when you arrived at your boondock in spite of vehicle charging.

I'd check the battery voltage if you have a meter for doing that.

Good luck!

 

[Bobbie54]

I don't think it could have been running. I unplugged the heater, didn't touch the fridge, went out and unplugged the house current. Did not re-enter the trailer.

I had just enough current to see fridge lights and the heater tried to start and then everything went out. So does seem like drained batteries are possible.

 

[Bobbie54]

I have a meter but am not sure how to check 12V charge across the two connected 6V batteries.

 

[Bobbie54]

If I am able to find a hookup- but the 12V system is out- will the fridge work? Lights? Headed off to find out.

 

[Centex]

I don't think it could have been running. I unplugged the heater, didn't touch the fridge, went out and unplugged the house current. Did not re-enter the trailer.

If your 3-way fridge is operating in 120VAC mode when plugged into the house power with propane off, when you disconnect the house power it will auto-switch to 12 volt mode unless you manually turn the fridge completely OFF.

Based on your narrative methinks your batteries took a big hit during your travel.

To check voltage on the pair of batteries while connected just put your meter probes on the negative post of the battery with the ground cable and the positive post of the battery with the power-out cable - that'll at least give you the voltage of the pair (your voltage of interest to start - looking for at least ~12v or better ideally).

If you are able to connect to full 30A shore power then all should work and your batteries take a charge - assuming your problem was depleted batteries. I'd put the fridge in propane mode to reduce that electrical load and increase the rate of battery charging.

Good luck!

 

[7Gentex]

.......... But behind the foam piece of insulation something is glowing yellow. See pic.

Sure hope that is an exterior marker/clearance light...

Still hooked up to the TV umbilical?

 

[Bobbie54]

Batteries are both at 6.53.

That glowing light tells me something has power anyway but is it possible they put the foam insulation (like you wrap plates in) over the 12V switch? If not, where could it be? The wire just goes through the foam and I'm afraid of disconnecting more stuff if I try cutting into the foam. Does the 12V switch have a light?


We did hit a few bumpy roads. And as it always does, the power cord sparked as I unplugged it. (It always does, no idea why, that's why I turned off the space heater first.)

 

[Bobbie54]

I guess the question is, what would shut everything off? If one fuse were out wouldn't some things work? Where else could the 12 V switch be?

 

[John in Santa Cruz]

Batteries are both at 6.53.
...

so, its +/red cable from RV to + on batt 1, - on batt 1 goes to + on batt 2, and - on batt 2 goes to RV -/black cable.

so you measure from the + terminal of battery 1 to the - terminal of battery 2, that should be 13.06V if each battery by itself is 6.53.

also, on your fuse panel, assuming you have the WFCO 8900 series electrical center I've got, remove the brown plastic cover (2 obvious screws), and examine the fuse panel, should look like this...

(my power converter was removed when I took this pic).

See the top silver block "NEG-" and the bottom silver block BATT+ measure the voltage between those, it should be the same 13-ish volts. The middle terminal, labeled +VCC, is where the output from the voltage converter goes (disconnected in my pic as I had removed the voltage converter), NEG- to +VCC should also be 12-13ish volts with or without the shore power.

if, with the shore power disconnected, you see voltage at the BATT+ ubt not at the +VCC, then check those two orange 40A fuses

if you do NOT seee any power on the BAT+ terminal, then find and check your battery disconnect switch.

 

[Centex]

Batteries are both at 6.53.

If that's each battery with no connecting cable between (and therefore no load on the batteries) the two the batteries are still suspect, IMO. That may be 'surface' voltage and not representative of what they can deliver under load.

Suggest you reinstall the cable between the batteries and check voltage as previously described across the pair (which is before the disconnect switch) or as described by John (which is after the disconnect switch), with some 12V loads turned on.

 

[Bobbie54]

Well, I can't do much of anything right now as it is dark. Probably not too cold tonight so we'll survive and maybe tomorrow with light I can locate a switch or spare fuse. I think for everything to go dead suddenly it has to be a fuse or a switch.

 

[oldwave]

another question do you hve an inverter? If it was on and the fridge set to auto it will go to inverted 120 volt and quickly deplete the battery (ask me how I know)

 

[Rossue2]

Check MyronL's post #7. That one is in my spare kit so haven't needed it.
https://www.escapeforum.org/forums/f9/no-electrical-power-11774.html#post226358

 

[Bobbie54]

another question do you hve an inverter? If it was on and the fridge set to auto it will go to inverted 120 volt and quickly deplete the battery (ask me how I know)

No inverter. And the fridge does not go automatically to 12V.

 

[Bobbie54]

Check MyronL's post #7. That one is in my spare kit so haven't needed it.
https://www.escapeforum.org/forums/f9/no-electrical-power-11774.html#post226358

It could be that. I had to replace it in my 15. Not something I can do right now but we're managing. Not sure with the heavy rain if we'd be staying charged if it were working! My trailer is wired a little differently since they moved the breaker box (and whatever goes with it) to the front. Driver's side is what I checked, fuse box is on passenger side though and I guess maybe the toggle switch is in there.

 

[Perry Butler]

No inverter. And the fridge does not go automatically to 12V.

Ours would automatically go to 12v if the gas was turned off.

Food for thought,

Perry

 

[Bobbie54]

Ours would automatically go to 12v if the gas was turned off.

Food for thought,

Perry

This one never has and I don't think my 15 did either. I have to turn it off for the ferry and I've never had it switch to 12v. And I didn't go near it. I think it is a breaker or a fuse. I'm at an agility trial though so no daylight time to troubleshoot and we're managing fine, just annoying to deal with. Thank goodness for the Jackery but I wish I had the big one here.