House lights have gone dark!

[Cathy Curtis]

Good morning.  I'm new, both at owning an RV and to this forum.  I'm quickly learning that I don't know anything!  I guess owning a motor home will do that to you.

i just acquired a 1983 New Horizon 20 ft motor coach.  I was sitting at the dinette yesterday afternoon when I heard a "pop", much like a circuit breaker tripping.  I'm plugged in to shore power so I checked the panel and cycled all the cb's and everything appeared ok.  However,  last night, my fourth night in her, I discovered all the 12v lights, including the range hood fan/light, were out.  The battery charge indicator shows way up in the green.  I started up the engine, then checked all the exterior lights, which functioned normally, so the problem seems isolated to the 12v circuit in the house.

This morning I found the fuse panel, hidden within the cb panel, and all of the fuses are good, so I'm stymied!  Is there another fuse panel in the New Horizon coach?

Yesterday was the first day I'd hooked up to shore power; could the electrical converter/charger/fuse and circuit breaker panel somehow be having a problem with the 110v, or is that a non-related issue?  (I can see how this could possibly be a very complex electrical issue, due to the multiple interactive systems, but I would prefer to get my lights working first before tearing out all the wiring and starting from scratch!)

Any suggestions or answers would certainly be greatly appreciated!  Thank you.   : )

[WME]

Check to see if your converter is putting out 12v dc.

There may be a CB in the converter that tripped. Older converters are a source of many problems.

IF your light went from full bright to full dark with the click then look for a CB in the power lead coming the battery.

 

 

Edited December 16, 2016 by WME

[Cathy Curtis]

WME, thank you for responding.  Might you suggest where to start looking for that additional cb?  The "click" sounded as though it were right here, inside, which is why I went to the only cb panel I've been able to locate, so far.

Btw, none of the 12v accessories were on at the time it tripped, which is why I didn't discover the "lights out" issue until hours later.

If it's the converter/main CB panel that has a problem (its the original 1983 OEM equipment) I surmise that simply replacing it is the only solution, right?  There is no 'fixing' it?

The thought just occurred to me that perhaps the battery isolator isn't working and the house battery could be in a low voltage condition?  Would that cause an auto-shut down of all the 12v accy's on that circuit to avoid draining the house battery too low?  I guess I better run to the store and buy a multimeter.

[WME]

Some of the older converters have a transfer relay that switches from the 12v battery to the 12v converter when the RV is plugged in. Unplug and see if the lights come on.

12v CB auto reset http://www.ebay.com/itm/20-Amp-12-Volt-Automotive-Marine-Circuit-Breaker-Reset-Short-Stop-Fuse-PACK-OF-4-/112067993530?hash=item1a17c5dfba:g:O3UAAOSwARZXk-fc

12v CB manual reset http://www.ebay.com/itm/CB41200-Sierra-Manual-Reset-Circuit-Breaker-5A-12V-DC-/132027807423?hash=item1ebd7876bf:g:z58AAOSwo4pYSJE~&vxp=mtr

These are the older style dc breakers that you should have in your coach. You may have one between the house battery and the fuse panel.

YES voltmeter by all means, Harbor Freight, Walmart places to shop for one.

Edited December 16, 2016 by WME

[Cathy Curtis]

Great advice!  Thank you, for that and the links....

Okay, I just went outside and unplugged the 120v.  The interior lights all came on!  Plugged back in, and they all went out again!  You are a certified genius!  (That's me, solving a problem!)   : )     I guess I need to buy at least two plug-in lights for times like these.  Thanks!  I've learned something useful today!

On my way to the store!

[Maineah]

It kind of sounds like the converter is toes up. The relay WRE was talking about is controlled by plugging the MH in. When it is plugged in the battery is disconnected from the coach and the power then comes from the converter but if the converter does not work you'll have no lights. Once you unplug the relay switches back to the coach battery and the lights come back on. Bottom line the problem most likely is in the converter/charger.

[WME]

Pics of your unit and a model. The relay is replaceable. But in all honesty a new converter is the answer to so many problems.

steps for replacement http://home.earthlink.net/~whemme/

This is the most  common old style converter, scroll down for a pic of the component layout to see where the relay is.

http://www.hayseed.net/~jpk5lad/RV Information/MagnaTek Pwr Converter/RV Binder1.pdf

You are about to have a new BFF, a new voltmeter

Edited December 17, 2016 by WME

[jjrbus]

Ditto and what Maineah and WME said.   The old style converters are very hard on batteries so the cost of a new one will be partially recovered on the first battery it saves.

I was going to add a link to "batteries do not die they are murdered"  but cannot find it, the old converters are mentioned in the article.   Jim

[Maineah]

Old converter/chargers had very poor charge voltage regulation they were slow chargers and would boil the water out of batteries if left on charge long term. The modern switching chargers devotes more current to the batteries resulting in a much faster recharge. Most now are 3 stage and will maintain a proper state of charge plugged in long term. It is a good inexpensive upgrade to an old MH. This is not a task for the inexperienced there is a fair amount of effort involved but it really is a great upgrade.