12 Volt Electrical Problem

[rmd230]

I have an elusive 12V electrical problem on my 2010 Entegra Aspire.
I have had my Aspire for three years. I had no problems during the first two years. During this past year I have had cascading problems that continue to get worse.

The following are the symptoms:
With the unit plugged into shore power;
If I turn on two or three of the halogen sets, the “low dc signal comes on on the refrigerator panel.
If I turn some of the lights off, the low dc signal on the refrigerator goes off.
With lights on, if I try to flush the rear toilet, which is a Tecma Silence Plus macerator and pump style, I get nothing. Thetford tech support has indicated the problem with the toilet is insufficient power.
The DC meter on the charger/converter reads 13.2 in float mode. When I start turning lights on, it drops rapidly down to 12.8, 12.6, etc. depending on how many lights I turn on.
I have replaced all 4 of the 6 volt house batteries.
I have disconnected the batteries and checked each with a volt meter. The result is approximately 6.6 each.
I have replaced all of the halogen light bulbs with LED bulbs.
I have searched for loose grounds or loose or damaged wires and have found none.

Does anyone have any ideas where to look next?

[vtbigdog]

Disconnect your house batteries from each other and let them site for 4 hours, then test again. I'll bet you have one bad battery or more.

[BFlinn181]

I agree, sounds like a bad 6 v battery. Letting it sit after disconnecting allows it time to equalize so you get an accurate voltage. I'd also haul them to a auto parts store that tests batteries for free and have them load tested. You said you have no loose grounds, but did you remove and clean them? Before removing batteries you might take some photos of your battery set up or map it out and label connections, they can get confusing trying to re install them.

[brobox]

Replacing 4 of the 6 six volt batteries could also be a problem. If one of the older 6V is weak, it will draw voltage from the new batteries make it appear good when it is not. In addition they will go bad before the new batteries and the problems will start all over again. As others have said, when there is a a rapid drop in voltage, one, or more of the batteries are bad. If it was a bad ground, you would not have high then low voltage, it would be constant low. I also like the individual load test method of checking batteries when there is a problem.

Good luck and let us know what you find.

[The Driver]

Originally Posted by brobox

Replacing 4 of the 6 six volt batteries could also be a problem.

The OP said he replaced "all 4 of the 6 volt batteries".

If batteries were the problem, it seems unlikely his symptoms would be the same after replacing them all.

It's interesting to me that his use of a pure 12 volt circuit (that runs straight off the batteries) causes a drop in the reading for the 120 volt circuit for the frig (that runs straight off shore power).

That's not exactly what he said, but I read that implication.

He did say the potty wouldn't operate after several light circuits were on. That makes sense, because the potty is a pure 12 volt running straight off the batteries.

What if his 12 volt relay is getting weak? He didn't say the lights would flicker and go off then come back, which is what mine did when the relay got old & weak (like me).

[BFlinn181]

Originally Posted by The Driver

It's interesting to me that his use of a pure 12 volt circuit (that runs straight off the batteries) causes a drop in the reading for the 120 volt circuit for the frig (that runs straight off shore power).

An RV refrigerator uses 12v in the controller that sets temp, switches from 120 v heating element to LP, LP ignition, display, and the interior light. A low voltage condition could cause controller to not work, thus the display warning.

All the problems described could be the result of one or more poor ground connections. Also check connections at the fuse panel for house.

[brobox]

Please excuse me, I misread the OP. I now see he replaced ALL 4 of the 6 V batteries and not 4 of the 6, 6V batteries. Back to reading comprehension 101 for me.

[rmd230]

Thanks to everyone who offered suggestions. After reading these posts as well as other web sites, I bypassed the battery disconnect relay with a heavy battery cable. This solved all of my problems. Obviously the relay was faulty. I have a new one on order.

[brobox]

Thank you for sharing the results. I'll bet you have helped others trouble shoot a problem.

[mccsix]

Just curious, did you use the disconnect much? I seldom use mine and I wonder if non use cause the contacts to oxidize?