No power

[Mopar_Earl]

You would only read 240v across the main. Everything else would be 120v only. One leg feeds one half of the breakers and the other feeds the other half. With the neutral, the RV is all 120v except the RV main breaker.

If your batteries are dead, your thermostats won't work to turn on the AC units. If you have an RV fridge it won't work without 12v either. Check all your 12v fuses and the converter reverse polarity fuses. Install a good fully charged battery and continue troubleshooting. Check the converter is getting 120v.


Earl

[MDC's First]

Thank you! This gets me on the path I was leaning towards. I think the dead batteries may be the culprit to all

[JimD]

First off if your battery is dead none of your 12 volt items will work whether you are plugged in or not. If the battery is so low as to crow bar (basically stop) any output from the converter that could be why no 12 volt things work. Still, this is just the second part of the equation to be looked at after you get the 120 volts working.

If indeed there is 120 volts from common to each bank of circuit breakers, then maybe there is a break between the common input and the mass connection of all outlet commons.

A circuit breaker panel is basically nothing but a bunch of switches that will trip if their current level is exceeded. I can see one breaker failing maybe but multiples at a time - very unlikely.

I don't know what an RV breaker panel looks like inside but have seen the insides of my house panel many times. There is basically a couple of buss lines that connect to one side of every breaker. When the breaker is not tripped the buss will connect through the breaker to the wire that leads to the outlet(s) that it is protecting. Each breaker is independent of all the others and 1/2 the breakers will be on one leg of your 240 and the other half will be on the other.

Another test is to measure one of your 120 volt outlets in a slightly different way. You should measure 120 volts across the 2 spade connections, which is normal. But, you also should be able to measure 120 volts from the hot side to ground. With the ground hole at the bottom, you should measure 120 volts from the right lug to the ground hole. Try it on one of your home outlets. If you measure 120 from hot to ground you definitely have an open common.

Can you post any pictures of your wiring setup?

[TCNashville]

Originally Posted by Mopar_Earl

If your batteries are dead, your thermostats won't work to turn on the AC units. If you have an RV fridge it won't work without 12v either. Check all your 12v fuses and the converter reverse polarity fuses. Install a good fully charged battery and continue troubleshooting. Check the converter is getting 120v.


Earl

This confuses me. If he's plugged into shore power all systems should work including 12V whether there is a battery present or not.

[JimD]

To illustrate my 12 volt dead battery thing let me relate a problem I had with the battery in my seldom used truck. I had left the truck alone for a number of months during which the battery got lower and lower. Totally my fault!

I put a good charger on it but the battery had gone so low that it would not allow any output from the charger. I had 2 different chargers one of which was fancier. That charger just would throw an error code before shutting down as it sensed that the battery was toast.

If you measure the battery and it is extremely low, you can disconnect one lead and plug in the converter. It should put out above 12 volts with no battery connected.

But be cautious. I had my battery disconnected in my 25 year old Lance camper and had it plugged in. I turned the fridge on and its control board promptly blew a power supply capacitor in half. Apparently the converter's output was higher, without a battery to help it regulate, than the fridge liked.

The 12 volt system should come up here once the 120 volt side is fixed, unless the battery is too far gone. I have been able to resurrect some vehicle batteries by using my charger. It has a battery recondition setting that somehow can bring some life back into a battery. That is unless your battery is just too low. This is speaking from experience.

[Mopar_Earl]

Originally Posted by TCNashville

This confuses me. If he's plugged into shore power all systems should work including 12V whether there is a battery present or not.

Not if there is no 120v power to the converter
Not if the neutral dropped out
Not if there is fuses blown on the converter
Not if the disconnect is opened
Not if the converter is bad
Not if the polarity is reversed (polarity fuses blown)
RV fridge requires 12v to work so at least 12v is needed for propane.
AC units require 12v for the thermostats to work, so 12v and 120v is needed for those to work.

He said his batteries are dead so he doesn't have 12v from the batteries. So if his converter isn't working, he wouldn't have any 12v shore or not.


Earl

[MDC's First]

Thank you. I'm a little confused about your last "test" suggestion. Shouldn't you read 120v between hot and ground? The same as between hot and common?

[Grumpy]

Didn't see this mentioned, but may have missed it.

Did you have the battery out? If you reinstalled it backwards you probably blew the reverse polarity fuse in the converter.

[MDC's First]

The batteries haven't been out. Right now I'm thinking I have an extremely low battery problem. I dont understand what this would have to do with AC power but that may be a tripped GFCI giving me a "dual" problem. Gonna go today and check these items. Batteries have been charging about 12 hours on trickle cycle.

[Vicr]

Lots of speculation and no answer. As with any electrical system unless you are skilled in troubleshooting and on site with a meter, trying to guess the problem is like throwing darts.

[MDC's First]

Vicr, while appreciate your input, I think you may be missing the point of this site. With all the "speculation" I hope to find an answer. As with most things in life. Should I come up blank, I will then contact a reputable RV technician. Thanks again

[Vicr]

Originally Posted by MDC's First

Vicr, while appreciate your input, I think you may be missing the point of this site. With all the "speculation" I hope to find an answer. As with most things in life. Should I come up blank, I will then contact a reputable RV technician. Thanks again

I'm not missing the point of this site. I'm an electrician and I see some bad information being posted here and some good, however as a professional it is my opinion that to troubleshoot electrical issues you really need be present with a meter and tools and a schematic of the equipment if available.

[Screwby]

As long as your mechanical inclined and use due caution when testing the AC side I’m all about DIY. I’ve seen what some of these “expert” RV technicians experience level is and it’s frightening. I have a slight advantage being over a decade in the building and service industry, but figuring it out and learning is my go to before I pay some stranger to do my work. If it’s something I’m utterly clueless about and don’t have the tools or desire to know then by all means I’m calling an expert. Unfortunately “experts” are few and far between in the RV industry and YouTube and Google have served me much better.
Be safe, be smart, go slowly as you learn double checking your method as you proceed and if it seems like your entering dangerous territory then stop and rethink your situation. Like I’ve always told clients, an ER visit or destroying the part your trying to fix is assuredly much more costly than a service charge would have been.

[Screwby]

Originally Posted by Vicr

I'm not missing the point of this site. I'm an electrician and I see some bad information being posted here and some good, however as a professional it is my opinion that to troubleshoot electrical issues you really need be present with a meter and tools and a schematic of the equipment is available.

Lol, agreed, I’ve seen some quite scary advice given

[JimD]

A few things.....

If you are trickle charging your battery, or even hitting it with a bigger charger, you should be able to simply measure across the battery and see the 12 to 14 volts there. If it is not at the battery then it will never be inside the coach.

If there but not inside it could be a battery disconnect issue which would have to be traced by following wiring provided you tried to cycle the reset. A wiring diagram would be helpful.

My Greyhawk manual says that if you hold the reset button for too long it quits working and you have to disconnect the battery to reset it. It is easy to know on mine because the switch area lights up when connected.

This should not affect the 120 volt side as they are separate but as you seem to have 2 separate problems, it won't hurt to work on one over the other.

As far as the 120 volt problem, a tripped GFCI should only affect a few of the outlets that are connected to it. I had the GFCI trip in my Greyhawk and it knocked out all outlets near the kitchen which is logical for a GFCI. It threw me for a bit as the reset was in the bathroom and didn't immediately come to mind.

As far as my comment about measuring 120 volts at an outlet, yes it will be measured from hot to neutral plus from hot to ground. Someone once told me to think of it as a magic "7" where it measures 120 across the top line of the seven and also down the right line of the seven. This has always stuck in my mind.

The comments from some members about scary information I hope is not referring to me. If it is, I apologize as I am just trying to assist with my extended background of electronic troubleshooting and classroom teaching. I try to explain how the circuit works and then what I would do to trace it. If this does not work for this forum, please let me know. No offense taken, I am just trying to help.

[Screwby]

My comment on scary info pertained to forums in general, not aimed at anyone.

There is nothing here that’s too scary to troubleshoot if the OP is inclined and knows how to safely use a meter.

[GHen]

I think I saw moparearl make a comment that may be important.

Have you switched the battery disconnect both ways and then checked your power? They are confusing and not always wired correctly. Turn it off, check everything, then turn it on and check.

[Snapchen]

Check the fuses on the converter. Mine had 3 25 amp fuses. All were blown when the tech accidentally shorted the house battery. Replaced the fuses and 12 volt system/charging was restored.

[ALJO]

AC controls are on 12 volt just like all the other appliances.

[camper Rick]

Check the small fuse in your thermostat. I spent hours checking everything in my system then found a two dollar fuse in the thermostat blown. Good luck.