Switching from shore power to RV battery power

[Kiwi&Major]

Now I am parked on a short crescent street not close to a shore power supply. Fortunately it is out of sight of a main street so it's good for a while. Plus Ontario is in a mandatory 14 day shut down mode so handing out parking tickets is not an essential service. The tip outs are extended & there is no power to bring them in even with the truck running. I put a meter on the battery which is less than two months old & got 12+volts. I looked @ all the fuses I can find & they are Okay. I don't see a big ones, a sort of 40-50 amp main fuse. I put a meter on the three short stops that I could find & they are all showing 0 resistance. I assume this means they are good. Is there a main fuse that I missed?

[Daryles]

Originally Posted by Larry LeBeau

All is good with shore power. Batt is good. Took out the batt connect switch and could not get any kind of reading on my tester in any of the 2 positions, but I'm not an electrician. Still no power to coach in Batt only mode.

Ok, shore power is good, battery is good.
just want to be sure we are talking about the 12v system (furnace, led lights, hydraulic system and gas water heater) works on shore power NOT when shore power is disconnected.
We are NOT talking about the 120vac system (residential fridge) which is powered by the battery via an INVERTER.
Ok, put the battery disconnect key back in and turn it ON. Make sure you are on shore power.
We are going to test your self resetting circuit breakers in the battery compartment.
They are the 50A red looking things. They look like buss bars but they are circuit breakers.
Put your multimeter black lead to chassis ground (the frame of the trailer or the negative terminal of the battery).
Pull the covers off the breakers. Set your multimeter for DC volts. Put the red positive meter lead to each post of the breaker one at a time. You should have 12vdc on each one since everything does work on shore power.
Safely disconnect shore power. Check each of the posts again. Again you should have 12vdc on each post.
If you don’t....the one that is missing 12vdc is probably faulty.
Link to Progressive Dynamics converter troubleshooting guides should you have to go that route.
https://www.progressivedyn.com/suppo...ooting-guides/

[Larry LeBeau]

I get 12v on all 4 with shore power, disconnect shore and I only get 12v on 3 of the 4. Will look on the web site to order part, Thx Larry

[Daryles]

Originally Posted by Kiwi&Major

Now I am parked on a short crescent street not close to a shore power supply. Fortunately it is out of sight of a main street so it's good for a while. Plus Ontario is in a mandatory 14 day shut down mode so handing out parking tickets is not an essential service. The tip outs are extended & there is no power to bring them in even with the truck running. I put a meter on the battery which is less than two months old & got 12+volts. I looked @ all the fuses I can find & they are Okay. I don't see a big ones, a sort of 40-50 amp main fuse. I put a meter on the three short stops that I could find & they are all showing 0 resistance. I assume this means they are good. Is there a main fuse that I missed?

Ok see other response regarding testing self re-setting circuit breakers.
ALSO… you mentioned you are in Ontario. Very cold up there. Lippert put out a bulletin to put the hydraulic system on an 80A breaker (the 80A one in the picture was added under warranty by Affinity RV Group).
Download the MyLCI app from Google Play store. It has a lot of good troubleshooting procedures, TSB (technical service bulletins), manuals etc. This includes procedures for manually retracting the slides. You can look this up on YouTube also.
There is also an Owners manual in the files section of this webpage. Page 18, manual instructions.
https://www.montanaowners.com/forums...?do=file&id=20

[beeje]

The disconnect switch is nearly useless. I have owned 3 trailers with that switch and have NEVER touched it on any of the 3 units.

[Kiwi&Major]

Thank you Daryles for your insight & the links. I didn't see the 80A breaker from your pic. We bought our Montana used from a previous owner who took it to Texas for the winter. He may not have seen the need to put in a bigger circuit breaker. I put a meter on both sides of the breakers & got 0 resistance so thought they were all good. I first saw a dimming of the lights when I test ran the furnace while on battery only. That was on Saturday & since then the lights started to dim shortly after the truck was shut off. The battery is less than two months old & is an RV specific model. It shows a full charge now but doesn't put enough current into the 12V circuit to light the LED's on the fuse panel when a fuse is pulled.

[Daryles]

The furnace draws 11A. If your lights dim and you are on battery power, your battery is weak BUT your 12v system IS working.
The lights dimming after your truck is turned off is a good sign, the truck to RV charging circuit is working. The dimming again points to a weak battery. Pull the battery and take it to an auto parts store. They can load test it properly.
You need a GOOD battery to run the hydraulic system.

[Kiwi&Major]

Because of the 14 day lockdown I can take it in for a test after that. It showed 12 votes on the meter. Crappy Tire really stands behind their stuff so a replacement is just a matter of the paperwork. Meanwhile I am still wondering if or where the line is open. Is there a bigger fuse in the circuit I am missing? Or is all of the battery current going to ground somewhere? The unit sat for almost a year & there were mouse droppings around the RV. Maybe they have chewed some wires that just started to contact the frame recently. This only started after we were on the road back from Texas.

[Daryles]

Sent you a PM

[jimcol]

Daryles is doing a great job leading you through the trouble shooting. I will offer this on batteries. Even a bad battery can show 12.? volts on your meter. That doesn't mean it is good because it still may not produce the power needed when a load is put on it. Only way to test a battery and know it is good is to load test it.

[Daryles]

So you dont have to wait 14 days for an auto parts store to open, take a battery out of your truck (my F350 diesel has 2) and put it in the rig. Test your slides and landing gear. Just for curiosity, run your furnace and see it the led lights dim with the truck battery in place.
Via my battery monitor mine shows 94A when operating my hyd slides and the voltage on the battery drops to 11.52vdc. That hydraulic system really pulls hard on a battery.

[Ahdmeyer]

you said you were away from shore power.if you can and have access to a portable gen hook it up and get a good charge on the battery. like i said in my first post mine were almost dead when i picked it up after the dealer had it, had my truck connected for 45 min to 1 hr and still could not lift the legs. relay just chattered until i got it hooked up to shore power then the hyd system worked.
took it home and charged it while on shore and everything is good.
al meyer
3931 fb
az

[Larry LeBeau]

All fixed $5.00 part, Thank you all for the help ….

[Ahdmeyer]

maybe if you were to let us know what the fix was it could possibly help someone down the line.
al meyer
3931fb
az

[Larry LeBeau]

working on trying to send pic

[Larry LeBeau]

here is a pic I replace one on the left. They are the same 50amp breaker

[Kiwi&Major]

Daryles I can't find your PM. We put the a boost onto the RV battery from my nephew's car & the slides ran right in. It seems that the RV battery is not taking a full charge from the truck alternator. I was able to drop the RV off @ my storage site but now am supposed to self isolate. The province has declared a state of emergency. That means I only leave the house for medical appointments or an emergency. I think my RV charging system probably doesn't meet that standard. I have until April 06 to think about it & text back & forth with you guys. Thanks for the help.��

[MrJull]

Hey Larry, Earl here - glad you found these guys. Pretty helpful huh? Like I said “ If it’s on a Montana and broke, someone’s fixed it and started a thread here for the rest of us!

[Eddiea]

Confusing, I leave it off. I installed a battery cut off switch on the negative side of batterie so when I store RV it’s off

[Lethbridge Sparky]

Originally Posted by Kiwi&Major

Is there a switch to change the unit from 110VAC that is going through the inverter to, I hope, charge the RV battery?

On much older units there was a switch but on today’s units as soon as you plug in the converter automatically switches to 120 volts and on most converters there is a charging circuit however it is generally a poor quality one.