12 volts issues

A voltmeter should reveal where the problem is. If you have 12.6 V at the batteries and much less at the lights or fuse box, the problem is between those two points. A long wire connected to battery negative and meter negative as you check a light voltage would be a good check for ground contacts. I would carefully check the voltage on each side of the battery cutoff relay or switch to see if voltage is lost there.

My batteries are charging properly from the converter, my MH was not used all winter but I start the MH engine once a month and I put my batteries on a benche with a slow charge.

The relay that switch 12 volts interior from converter to batteries maybe the problem, were is that relay located within the converter ?.

I don't know the model of my converter I don't see any tag with name or brand but it is the original converter(1982 citation MH)

Could be a poor/bad ground. It's rather common for the cable where it hooks to the coach frame to go bad.

Dusty

Welcome Dan!

It sounds like the relay that switches your 12 volt interior power from that produced by your converter back to getting it straight from the battery is sticking.

Has your m/h been sitting parked for very long?

When I first bought mine I had a similar problem, but it didn't happen every time. To solve it I hooked the shore power line up to an extension cord plugged into a digital timer set to go on and off every hour. The constant 'exercising' of the relay cured it sometime during the week it was hooked up that way. It's never happened since.

What converter model do you have?
How low does the battery voltage get while in storage?

dancouture10 wrote:
I did not explain myself properly, the problem is not with the fridge but with all the volts supplies to the interior lights not properly, the system does not seem to switch from Ac to Dc, only atfter a long period of time like 12hrs or so ?

Not sure about all that you are asking, but it seems like the converter is providing 12 volts to your lights while plugged in, but is not charging your battery. If you start the chassis engine, the alternator charges your coach battery and after a period of time it is charged enough to provide interior lights. Could there be a faulty ground or a disconnect switch that is not working while plugged in to 120 volts?

I did not explain myself properly, the problem is not with the fridge but with all the volts supplies to the interior lights not properly, the system does not seem to switch from Ac to Dc, only atfter a long period of time like 12hrs or so ?

Fridges operating on 12 volts DC without engine runnning or when not plugged into camp/shore power, need a good fully charged house battery to start with and quickly run the house battery down. If working right, the fridge should be set to 12 vdc mode only while you are driving or when plugged into camp power.

What refer are you trying to get working? 99% of RV refers are dual 120VAC/gas. There are very few three way refers out there.