First time out electrical problems Coach Batteries lose charge on Shore Power

JoePa77 · 07-08-2019, 06:57 PM

New Forester 2020 2861ds, went away for a weekend to try out our new toy. I admit right up front we are newbies to camping/RVing world. We had the camper plugged in all week leading up to the trip, running the refrigerator and anything else we needed on shore power and one solar panel on the roof. No problems.

The second morning we woke up and the lights were dim and the refrigerator was not working. I started the RV and then the generator separately and the lights got bright and the fridge worked. We went on a bike ride and visited a few other places come back to the RV and did not think of anything (since we had no experience to check on things). Slept and repeat biking, visiting friends, etc the next day - got back around 11:00 PM and basically nothing Coach V around 7.2 V and nothing working. Called FR line to talk to a technician, since I have only owned for one week it took a while to get confirmed as an owner... So around midnight I was talking to a technician and he suggested turning everything off at the kill switch and when stores open get a battery charger to trickle charge the batteries so they don't get ruined. Which I did and the last two days went fine with the trickle charge.

No problems with the three hour drive home, coach batteries above 12V on monitor. Plugged in again back home, 24 hours later still reading 12V.

It seemed to me to be a converter problem at the campsite, but now everything working again. Can anyone help diagnose my issues? I will be trying a real trip in three weeks and would not like a repeat.

cavie · 07-08-2019, 07:02 PM

Quote:

Originally Posted by JoePa77

New Forester 2020 2861ds, went away for a weekend to try out our new toy. I admit right up front we are newbies to camping/RVing world. We had the camper plugged in all week leading up to the trip, running the refrigerator and anything else we needed on shore power and one solar panel on the roof. No problems.

The second morning we woke up and the lights were dim and the refrigerator was not working. I started the RV and then the generator separately and the lights got bright and the fridge worked. We went on a bike ride and visited a few other places come back to the RV and did not think of anything (since we had no experience to check on things). Slept and repeat biking, visiting friends, etc the next day - got back around 11:00 PM and basically nothing Coach V around 7.2 V and nothing working. Called FR line to talk to a technician, since I have only owned for one week it took a while to get confirmed as an owner... So around midnight I was talking to a technician and he suggested turning everything off at the kill switch and when stores open get a battery charger to trickle charge the batteries so they don't get ruined. Which I did and the last two days went fine with the trickle charge.

No problems with the three hour drive home, coach batteries above 12V on monitor. Plugged in again back home, 24 hours later still reading 12V.

It seemed to me to be a converter problem at the campsite, but now everything working again. Can anyone help diagnose my issues? I will be trying a real trip in three weeks and would not like a repeat.

Camp shore power on and working?? Main breaker on in the RV?

JoePa77 · 07-08-2019, 07:06 PM

Yes, the shore power worked, the AC worked fine. I could us the Air Cond and Microwave. I had a surge protector that showed 120+V and 60 Hz. Depending what was running on the AC the amps would vary.

All the fuses in the panel were good. No circuit breakers had tripped.

CHICKDOE · 07-08-2019, 07:11 PM

what type of refrigerator do you have? rv or residential? if residential if could be as simple as the refrigerator is running the batteries down overnight.

JoePa77 · 07-08-2019, 07:16 PM

I have the standard RV refrigerator the Domico that runs on electricity or propane. The fridge at this point with the low voltage would not run on propane either.

ScottBrownstein · 07-08-2019, 07:44 PM

I would think you have a converter (or had...) Unfortunately your narrative isn't sufficient to totally diagnose that. You say you started your RV and then the generator. First off, you could start the RV so the engine battery was OK. You started the genny which may or may not use the chassis battery. Then the voltage came up. Well, once your engine was running, the alternator would begin to charge the house bank all by itself, without the need for the converter. The genny, on the other hand, would have used the converter to charge anything. Not sure if your converter began to run or if the engine did the heavy lifting. Nonetheless, when you shut off the battery master switch, the converter would have still supplied power to your 12 volt accessories anyway. If you were dark...your converter wasn't running.

But...now it is! I love an intermittent problem.

ScottBrownstein · 07-08-2019, 08:15 PM

but...you have learned a good lesson here.

When starting up the engine...look at the DC voltage panel and make sure it goes up above 12 volts

When plugging in to shore power...look at the DC voltage panel and make sure it goes up above 12 volts

When running your generator...look at the DC voltage panel and make sure it goes up above 12 volts

You will never be surprised with dead batteries

tlf65 · 07-08-2019, 08:42 PM

In your house fuse panel there are a couple of 30 amp fuses that connect the house batteries to the converter make sure those arn't blown or missing.

JoePa77 · 07-08-2019, 09:23 PM

Thanks everyone for all the tips.

tomkatb · 07-09-2019, 07:29 AM

Got to learn much more about electricity!!!

You need a quality voltmeter connected to the house batteries. Saying you have 12 volts does not help.

A fully charged battery is 12.6 volts. Non usable battery is 12 volts.

When charging or just after charging batteries read higher than 12.6 volts. The converter charges at voltages from 12.8 to 14. Depending on battery status.

Your issue is what is the problem. No way enough information to check much.

Could be the converter, battery charger, could be bad batteries. Could be goofy wiring. Could be items on you do not know about.

RV’s are very complex.

There are no decent manuals nor wiring diagrams.

When taking a voltage reading carefully state what is going on. I.E. After sitting on the shore power all night disconnected it is 12.5 volts. Dead battery, charging on shore power 14 volts, and I can hear the converter fan on, etc.

ScottBrownstein · 07-09-2019, 08:30 AM

Quote:

Originally Posted by JoePa77

Thanks everyone for all the tips.

When I said 12 volts I was being relatively generic. I am sure that your coach has one of those little LED panels for tanks, propane and battery. If you look closely, the bottom 3 LEDs on battery say percentages...they are pretty much junk! The top LED, however is not 100% it normally says charge and will light when your voltage is ABOVE 12.6, meaning that something (alternator or converter) is charging the bank. Keep an eye on that and you won't be surprised.

Since your coach is new, something simple is wrong...

CGK · 07-09-2019, 02:12 PM

X2 on the likelihood of a converter issue. And since it is intermittent, it could be something as simple as a loose wire. Best of luck with the new MH!

JoePa77 · 08-21-2019, 05:45 AM

Just to complete the thought for all those with suggestions. Before my big trip of the summer I went and had the batteries checked... both were bad and not holding their charge. So we replaced them and have been doing well ever since.

JoePa77 · 11-05-2019, 08:19 PM

After two plus weeks on the road in August, Motorhome was at the dealership for 6 weeks got it back and got ready for another weekend trip. Plugged it in on Tuesday to get the refrigerator ready to go and enjoy a weekend trip. On Friday morning had the repeat problem, lights dim refrigerator not running, generator would not start. Had to plug in the trickle charger again to get the power back up. Went to have batteries checked, they were good but obviously needed charged. Kept the trickle charge going while on shore power but everything worked as expected while off shore power all day Saturday. I did check the monitor when plugged in while at home before the trip, battery level was maintained (even without being plugged in for two weeks) until I ran the refrigerator for a few days.

Still have to figure out what it can be.. but I will get there.

CGK · 11-06-2019, 11:10 AM

Thanks for the update - sorry things are still not as they should be. Sadly, we have little more information with which to work than before. The fact that your batteries were bad and that the replacements seemed to correct the situation is not a surprise....batteries can only take so much "abuse" and if they are discharged too far and/or too often they will fail. The replacements are fresh, and it appears all is well - but in the long run, all is NOT well (as you have reported). The dealer had the coach for 6 weeks - did it offer any ideas as to what could be wrong? Your last update does offer a few more clues: (1) if shore power does not keep the batteries charged, and a trickle charger direct to the batteries does; and if everything works properly after the trickle charge - then it still appears there is a problem with the converter/battery charging function. This was mentioned as a possibility before, and there were some suggestions as to how you might check to confirm it is/is not working properly, (2) if the battery was maintained with little apparent loss of charge for 2 weeks while parked and not receiving a charge from the trickle charger or converter, it would seem you might not have a short in the system or major parasitic draw on the batteries; although you did not mention if you had the battery disconnect on or off during that time (I suspect it was in the disconnect mode, since normal parasitic draw would reduct the battery charge over a two-week period if the batteries were not receiving some type of recharge current), and (3) when you plugged-in prior to your trip and a few days later you were again out of juice, it would indicate that the batteries are indeed not being adequately charged through the converter (via shore power) and/or there is a major draw on those batteries (a much less likely possibility is that the wiring is such that when you are on shore power it actually depletes the batteries - I can't picture how that could happen, but am going by the clues you have provided). You say you'll get there, and that's exactly the spirit needed for this type of troubleshooting. It is frustrating, but highly rewarding when you identify and fix the issue. This one is a bit more baffling than most, but I'm afraid it's back to the basics again. Your EMS told you the campground shore power was going to the coach, so that doesn't look like the problem, although you didn't mention using that device when plugged-in at home (you should). So that takes you back to the charging function, the wires/breakers associated with the batteries, and the draw on those batteries. Oh, and since you've depleted those batteries again, you may need to have them tested again, since they won't take a charge and be able to provide necessary 12V power if they have been compromised. I agree with those who say it should be a simple solution, but the troubleshooting to get to that solution has been difficult. Hang in there, and good luck!

**Bama Rambler** · 11-06-2019, 12:01 PM

One thing to do is check (or have somebody that's capable check) for 120 volts going to the converter at either the breaker or the converter itself. That will tell you if the converter is getting power.

tomkatb · 11-06-2019, 12:36 PM

If the converter is operating properly, max charge voltage would be near 14 for a half hour. Also you would hear the converter cooling fan running.

Then as the battery come up the fan goes off and voltage will drop to 13.5 for however long it takes. Could be days if you are living in it.

Stage three of the converter is a 12.9 volts or so. Trickle charge.

That is how to verify the converter is operating.

If you do not see those voltages likely the converter is broken or a fuse somewhere is blown.

I suspect this is the issue.

TitanMike · 11-06-2019, 04:08 PM

Quote:

Originally Posted by tomkatb

If the converter is operating properly, max charge voltage would be near 14 for a half hour. Also you would hear the converter cooling fan running.

Then as the battery come up the fan goes off and voltage will drop to 13.5 for however long it takes. Could be days if you are living in it.

Stage three of the converter is a 12.9 volts or so. Trickle charge.

That is how to verify the converter is operating.

If you do not see those voltages likely the converter is broken or a fuse somewhere is blown.

I suspect this is the issue.

Everything I've read so far is pointing to the fact the batteries are not being charged by the converter yet the converter itself is still working. (generator started the lights which are 12 v work).

First stop for me would be the reverse polarity fuses at the converter (look carefully, they're marked) or the Battery isolator system that routes charging current from coach alternator or converter.

A good Multi-Meter is essential if one is going to self diagnose an RV electrical system.

JoePa77 · 11-09-2019, 08:55 PM

Thanks one and all for these great suggestions. It has been very cold here in northern Ohio since I posted Wednesday, tomorrow is supposed to be in the 50's so I can pull out my meter from storage and try to get some readings where I can gain access. I definitely can access the coach batteries so there is a lot to be learned there. Some of the other suggestions I will search this forum to find out where I can access them. I have hooked up shore power again because I had not turned off the elec shut off for the season, the solar did not keep up and the battery power was very low again. After I hooked up shore power I ran the separate trickle charger on the batteries for one night. The batteries have remained charged on shore power, again with nothing much running and the switch turned off.

Will update any voltages I can measure tomorrow. I am very appreciative of all your inputs helping me learn about the greatness of these engineering marvels. I do not have much expertise yet, but am very ready and eager to learn all the little gems of wisdom everyone shares on this forum.

TitanMike · 11-09-2019, 09:20 PM

Quote:

Originally Posted by JoePa77

Thanks one and all for these great suggestions. It has been very cold here in northern Ohio since I posted Wednesday, tomorrow is supposed to be in the 50's so I can pull out my meter from storage and try to get some readings where I can gain access. I definitely can access the coach batteries so there is a lot to be learned there. Some of the other suggestions I will search this forum to find out where I can access them. I have hooked up shore power again because I had not turned off the elec shut off for the season, the solar did not keep up and the battery power was very low again. After I hooked up shore power I ran the separate trickle charger on the batteries for one night. The batteries have remained charged on shore power, again with nothing much running and the switch turned off.

Will update any voltages I can measure tomorrow. I am very appreciative of all your inputs helping me learn about the greatness of these engineering marvels. I do not have much expertise yet, but am very ready and eager to learn all the little gems of wisdom everyone shares on this forum.

Even before you start reading voltages start with the reverse polarity fuses. Below is a picture of the most common Power Center Fuse/Circuit breaker panel in Forest River RV's. The Reverse Polarity fuses are the two red 40 amp fuses near the center of the picture:

If you have a remote (floor mounted) converter/charger the reverse polarity fuses are located here (on most of this type)

Might save you a ton of time.

An added note:

All the other fuses have a red LED that lights up when the fuse is blown. Unfortunately these two do not. It pays to pull each of these fuses and check for continuity with your ohm-meter. Every once in a while fuses fail without the visible burnt center. Same result.

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