Help! No 12-Volt Power on Batteries

BeatsWorkin · 08-12-2017, 04:38 PM

I stupidly waited until the last minute (I leave tomorrow) to hook the batteries back up to the trailer and I can't power to any of the 12-volt devices (lights, CO2/Propane detector, radio, etc.) except when I'm plugged into AC power from the house.

I have a JayFlight 154BH.

After reading through some previous threads, I came up with a complete list of items I checked that were mentioned. Here is what I checked:

1. I hooked up the batteries in parallel as usual and they show 12.63 volts each on the meter so I should get something.
2. I made sure I had the white wire that is grounded to the frame on Negative and the Black/Green wire on Positive. (At one point I think I got that backwards and corrected it.)
3. I checked the 30AMP fuse that's about a foot down the line from the Positive wire and it's fine. I even replaced it with a new one and still nothing.
4. There are no tripped breakers or bad fuses on the box under the dinette bench.
5. The one GFCI outlet was not tripped.
6. With the AC power connected and the batteries disconnected, I checked the output TO the batteries for recharging and it was at between 10.8 and 11.8 volts. I should be getting 13.6, shouldn't I?
7. With the AC power DISconnected, I got zero voltage coming out on those same wires.
8. When hooked into my truck, the truck battery does still activate the lights as necessary.

So, what am I missing? I'm not an electrician and I have a small multimeter but I only know how to do basic things, like check voltage, because someone showed me how.

I'll still be departing tomorrow (though perhaps later than planned) and I will have AC power almost everywhere on this trip, though I do have a couple of Walmart nights planned and I don't have a generator. It would be nice to have at least one working fan when it's too warm.

Thanks much in advance for any help. If nothing else, I'll try to fix it while on my trip. I have a tight schedule so I can make it to western Nebraska for the Eclipse on the 21st.

Grumpy · 08-12-2017, 04:42 PM

If you had it backwards you probably blew a fuse in the converter. Don't think the converter will put out 13v without the batteries connected.

**Mustang65** · 08-12-2017, 05:16 PM

Quote:

Originally Posted by BeatsWorkin

I have a JayFlight 154BH.

2. I made sure I had the white wire that is grounded to the frame on Negative and the Black/Green wire on Positive. (At one point I think I got that backwards and corrected it.)

If you connected the WHITE cable to the POSITIVE battery terminal and the BLACK cable to the NEGATIVE battery terminal post, you probably blew the 2 reverse polarity 12VDC fuses in the panel. Look at the fuse layout on the controller door. They should be 30Amps each.

Don

My Registry

RVing with SOLAR

BeatsWorkin · 08-12-2017, 05:40 PM

Quote:

If you connected the WHITE cable to the POSITIVE battery terminal and the BLACK cable to the NEGATIVE battery terminal post, you probably blew the 2 reverse polarity 12VDC fuses in the panel. Look at the fuse layout on the controller door. They should be 30Amps each.

Don, there was one that was marked as a polarization fuse. It was 40 amps, which is weird since I only have a 30 amp connection. I replaced it and nothing changed. Above it was a 30 amp fuse and I replaced it as well. Still no change. Light is failing and a thunderstorm is on the way, so I'll change all the rest of the fuses tomorrow. Every fuse I changed looked like it was still good and the elements were connected.

Thanks for the quick reply. Hopefully I'll have other suggestions tomorrow.

BeatsWorkin · 08-12-2017, 05:43 PM

Grumpy, thanks much. Fuses changed (they looked fine but I replaced them anyway) and it still doesn't work.

Isaacs · 08-12-2017, 07:26 PM

Doesn't the 12V converter plug into the back of the 120V panel? I don't think you can see this unless you remove the panel. Perhaps that receptacle on the panel is not working. Fuse? Breaker? Not plugged in properly?

Isaacs · 08-12-2017, 07:31 PM

Another thought; perhaps when you stuffed the power cord back into the trailer it coiled up in such a way that you knocked the plug for the converter loose.

Isaacs · 08-12-2017, 07:33 PM

Oops--never mind. You have power from the converter--my bad!

SkyBound · 08-13-2017, 08:04 AM

Just for troubleshooting, do you have a different 12V battery you could hook up? I know your current ones read OK but who knows.

When the battery gets hooked up backwards, crazy things happen. I just went through this with someone else's trailer. The reverse polarity fuses ended up being blown, but only after a couple days of normal 12V use and operation. The reverse polarity fuses are either 30A or 40A, and on this converter there were 2, one on top of the other.

Maybe also check your grounding point on the frame to make sure it's still connected and not all rusty.

BeatsWorkin · 08-13-2017, 11:06 AM

Skybound,

I have two batteries and they are both good and tested elsewhere. I tried hooking up to both batteries in parallel and each battery separately. I put them back on a charger and got them both up to 13.6 volts and still it didn't work.

As you said, I'm sure something "crazy" happened. I've replaced the reverse polarity fuses on my panel and also the 30 amp fuse in the wire between the battery and the interior panel. None of the ones I pulled looked like it was blown but I replaced them all anyway.

I didn't think about the grounding point and I just went and checked it out. It's fine. No rust. I cleaned them a bit regardless and still I have nothing.

I'm leaving on my trip this afternoon and will hopefully figure this out when I have a few days in one campsite and, hopefully, more knowledge on how to troubleshoot the problem. At that point, if I don't have it figured out on my own, I'll take pictures of everything and perhaps someone can point out something that I'm not noticing.

Thanks again and regards,

bedrck46 · 08-13-2017, 11:56 AM

Remove the 30AMP fuse that's about a foot down the line from the Positive Terminal.

Then test each side of that fuse holder. Make sure your battery is connected and you are also connected to shore power. Connect one lead of your meter to a good ground and then take the other lead and test the contacts in the fuse holder You should read 12 volts+. on those contacts One side would be from the battery and the other side would be from the converter
Just thinking that the green wire from the battery to the fuse holder is bad .

SkyBound · 08-13-2017, 12:18 PM

Also flip open your converter and use a multimeter set to VDC - put one lead on the + side where the battery cable attaches to the power distribution board and the other on the - side where the white grounding cable clamps into. If there is no voltage there then your problem is upstream of the converter, somewhere between that and the battery.

BeatsWorkin · 08-13-2017, 06:12 PM

Bedrck46 and SkyBound,

Thanks for the troubleshooting advice and explanations of how to use my meter. I'm learning something new every time I work on my trailer.

I'm overnighting at a Walmart tonight and I can do without power tonight. I even have a jug of water available for flushing since the pump isn't working along with everything else. I'll check out these steps after I get settled tomorrow for a couple of days at Wright-Patterson AFB.

Thanks again. I'll let you know how it goes.

bedrck46 · 08-13-2017, 06:24 PM

Take a look at the green wire It connects to the Pos battery terminal then thru the 30 amp fuse then it should connect to a few wires with a wire connector That could be a bad connection or it may have come loose.

bedrck46 · 08-13-2017, 06:46 PM

Also check the back of the converter to make sure nothing came loose and while you are there tighten all connections

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