Strange electric issues

[Brutas]

We have a 2001 Newmar Mountain Aire gasser on a F53 chassis. Yesterday I went to the stoarge unit to exercise the generator. I leave it plugged into 120v shore power when not in use. When I got there I unplugged it, checked the coach batteries and all was fine. Then I ran the generator on heavy load for a little over an hour. When that was over I shut down the generator and had no battery power. So I plugged it back in for about 20 seconds and when I unplugged it again I had full battery power. This happens repetitively. No battery power but if I plug it in for a short period the batteries come back. Anyone recognize anything here? Thank you

[Jyrocharlie]

My first thought, check the battery terminals. When it has no power, use you meter on volts and go from each battery post to the terminal and see if you can find where you losing the voltage. That's the easiest to fix and most common problem for vehicles in storage.

[Rkesselus]

on some units if you have a salesman switch, battery disconnect, it controls a solenoid and it supplies voltage to a gang of multi-breakers some that automatically reset and some that you have to manually reset. You may have a multi-breaker in that system that is opening and then resetting when it cools some. Just a thought not knowing your system.

[Bahamaniac]

Transfer solenoid is sticking.

[twinboat]

What is that ?

Originally Posted by Bahamaniac

Transfer solenoid is sticking.

[twinboat]

Take the battery terminals off, clean them and reinstall. Don't just look at them, even if they look OK, remove, clean & tighten.

[Ray,IN]

Originally Posted by Bahamaniac

Transfer solenoid is sticking.

Do you mean transfer switch? If so, I agree. The sticking is caused by unknowing owners switching power sources under heavy loads, which burns the contacts.

[Robbr]

No power coming out of ems board to my front AC unit any ideas

[Brutas]

Where is the transfer solenoid on the Mountainaire?

[twinboat]

Your having a 12 volt issue. It has nothing to do with the auto transfer switch. That switchs between shore power and generator power, not battery power.

Plugging it in starts the battery charger. The charging of the house batteries may be burning thru a bad or dirty connection making it connect.

You say you plug in and all works. When you unplug it still works. How long does it work ?

[Brutas]

When I unplug from shore power the lights do not work. Sometimes they come on later. Last time we were out they came on about 10 minutes after unplugging. When we got back to the storage garage they were still working but when I went back the next day there was no power again. Batteries always show full charge throughout all this on the multimeter.

[arcaguy]

When you are having 12 volt issues check the ground, if it looks good, check it again. The vast majority of 12v issues can be traced to a bad ground from the battery to the chassis, especially on older coaches. Usually this is a simple as following the negative battery cable to a place where it is bolted to the frame. Remove the cable, clean both sides of the connection to shiny metal and then start trouble shooting other issues if your problem isn't solved. Good luck.

[Brutas]

Here's the latest. The batteries continue to power the lights and stairs for anywhere from 30 seconds to 5 minutes after unplugging from shore or turning off the generator. Voltage at the batteries is 12.5 v. At this point I checked the converter with the multimeter. registered only about 2 v coming out of the converter. Jumps up to 12.7 when plugged in. Sound like a bad converter? I have 2 IOTA's DLS-45 in parallel.

[twinboat]

Nothing comes out of the converters unless they are plugged in. They send out charging voltage to the batteries.

If your seeing 2 volts without being plugged in, that's a problem. The wires hooked to the converters go to the batteries. You should see battery voltage.

I think your going to have to find the battery disconnect switch and jump it.