Alright, so after replacing my batteries I thought that our problems were solved. Especially when we arrived after two weeks to fully charged batteries in the storage yard(The refrigerator was hot however as it's fuse apparently blew :(. It was not to be. Again today when we arrived to the park our batteries were only reading 12.5v. I was thinking maybe it was the refrigerator doing something crazy since with the blown fuse our batteries were showing a amazingly full 13.2v at 2 am after two weeks on solar alone.So I broke out the multi meter and tried to track down any leakage and I got a bit of a surprise. When I touched the negative post to the negative wire I only got .75 amps or so but when I touched my ground wire it was reading 10 amps. That was on top of a bit of sparking when I removed it. Can this be the cause of my battery drain?I've got to admit I'm a bit confused at this point ;) From some reading I take it this is called a hot ground but I'm not sure what to do about it. I tried pulling all the fuses and putting them back in one by one but it seemed that anything that was on would increase the amps through the ground. How do I fix this?Thanks(as usual) for the help,Tim CzarkowskiTotatTravelers.Com

Not sure I would be trouble shooting using current flow or ammeter setting. Especially since you mentioned blowing a fuse. A shorted appliance and using an ammeter can damage the meter. You can use the voltage scale and easily locate an open ground. If you have an open ground most likely problem is where it connects to the frame. Either at the battery end or the appliance end. Measure voltage across item in question. If no voltage move the negative probe to the battery terminal negative post. If you have voltage the ground is open. If the fridge worked before and blew a fuse could be a bad circuit board. If the fuse is blown I would remove the positive lead from that board, replace the fuse and measure the voltage. from the positive wire you removed and the ground on the board. If you measure 12 volts you have a problem with the board. In fact that is the test I would try first. Hope that makes sense.

How are you testing the battery? A full battery should be 12.6 volts. 13.2 is a common voltage for a charger to be sending the battery.

This is from my batteries, the 12v DC system. With the ground wire off all my 12v equipment stopped working. From the negative terminal to the ground with all the fuses in I was getting 10 amps or so. From negative terminal to negative wire I was getting 0.75 amps. This seems clearly wrong from what I have read and sounds like a hot ground. However I'm confused, as I said above. I just want to be able to boondock without watching my batteries rapidly discharge. Tim Czarkowski Totaltravelers.com

I am using a panel from my solar controller. The 13.2 reading was at 2am after two weeks unplugged in a storage yard I assume the panels had brought it up to that point that day. Previously after a day of towing I'd get a reading of 14.4 which would then fall to a more normal 12.9 after being disconnected. Something is discharging my batteries. Even while towing or in the full sun on my 200w of solar the batteries are dropping. As I said I thought it was something with the fridge but testing with the multimeter made me think maybe it is something else. Am I correct in that the reading from negative terminal to ground should be 0 amp or very close to it? It seems weird to me that nothing would run without the ground and that there appears to be 10 amps running through it. Still confused :(Tim Czarkowski Totaltravelers.com

to me it sounds like your NEG-ground connectionis NOT grounded at the frame, the wire is broke, or the fram connection corrodedwhen you put the meter directly between negative and frame ground you supply a clean good pathyes 10 amps is high for parasitic loadscould be a bad control board on the fridge, or something elsefix your neg to frame groundthen track down you loadi would pull the DC fuse for the fridge for a starterthen the rest

Hot Ground??? | Good Sam Community

buylow12
Explorer
Aug 15, 2015
So how can I test between the battery and that fuse? You have to be correct, I'm just not sure what to do about it.

Tim Czarkowski
Totaltravelers.com
Chris_Bryant
Explorer II
Aug 15, 2015
buylow12 wrote:
Alright I tried checking that by using my multimeter on the OHM setting and it seems to be working properly. I tried both of the wires on that block just to be sure and got the same result. It was reading anything from 0.00 to 0.04 which I believe is right.

Is there anything else I can try? There was a blue wire that ran to nothing but I don't see how it could short anything out. You can see it on the far right about midway up.

Tim Czarkowski
TotalTravelers.com

That fuse on the bottom left should be a 3 amp fuse, and it is the first thing in the refrigerator, so the draw must be before this- not in the refrigerator itself.
buylow12
Explorer
Aug 15, 2015
Alright I tested the ground cable also. Same result, no resistance. It has to be something between the batteries and the control panel on the fridge but I'm not sure how else to check it.

Tim Czarkowski
Totaltravelers.com
buylow12
Explorer
Aug 14, 2015
Yea, about that...... I think I was just confused about the fact that the negative is the ground in a 12v system. The 0.75 reading was actually the solar panels I believe. I'm working on my minor in 12v, on short notice, lol.

Tim Czarkowski
Totaltravelers.com
wa8yxm
Explorer III
Aug 14, 2015
I am not sure I follow your testing.

When I touched the negative to the negative wire I got 0.75 amps but when I touched the GROUND I got 10

On the 12 volt side of life.. The chassis ground is the negative.. What "Ground" did you touch? If it was an A/C ground I'd need more info but I would suspect a false reading.. Many ways that can happen.
buylow12
Explorer
Aug 14, 2015
You know, I actually haven't other than getting the 9.5 amps with the fridge on and the 0.223 amps with it off. I didn't test it with the setting on ohms however. It is short, heavy, and appears intact. I don't know what else to try so I'll certainly test it as soon as I get back.

I'm going to be a 12v pro by the time I get this problem figured out. I've got so much time involved now I have to figure it out without getting a tech involved, it's a matter of personal pride, lol.

Keep em coming,

Tim Czarkowski
Totaltravelers.com
MrWizard
Moderator
Aug 14, 2015
what about your main battery neg frame ground cable have you checked it out
buylow12
Explorer
Aug 14, 2015
Alright I tried checking that by using my multimeter on the OHM setting and it seems to be working properly. I tried both of the wires on that block just to be sure and got the same result. It was reading anything from 0.00 to 0.04 which I believe is right.

Is there anything else I can try? There was a blue wire that ran to nothing but I don't see how it could short anything out. You can see it on the far right about midway up.

Tim Czarkowski
TotalTravelers.com
Chris_Bryant
Explorer II
Aug 14, 2015
It has to be in the wiring before the fridge- or at least before the circuit board, which should have a 3 amp 12 volt fuse.- It could be a short in the recall wiring, which is between the white terminal block on the back and the circuit board.
buylow12
Explorer
Aug 14, 2015
Yes, the ground attaches to the frame in the battery box. How would I go about testing the ground with the VOM, both at the battery and at the fridge?

I took the cover off the fridge and it has both a 5 amp and a 3 app fuse so how it could pull more than that I don't know. Seems it must be something with the wiring for that to happen. After the shocking revelation that the ground and negative are the same in a 12v system, I feel confusion coming back, lol.

Tim Czarkowski
Totaltravelers.com

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