Bounder: No electrical power to our 2012 Bounder 35Kand all three batteries are dead

[VincePAC]

Hey, everyone. Was going to ask for ideas. We have a 2012 Bounder 35k. Have not had any problems with it until September, when the steps quit working. We brought it to our shop. They had to replace the motor. While it was there, i had them replace the switch located just inside the door because the little light in it did not work (I want everything to work!). One night while at the shop, it got into the 20’s. The coach was plugged in to shore power at the shop. They had the propane furnace running to keep it warm. We went by to check on it once the temp was above freezing again. We only had random overhead lights inside. We were all perplexed and there were three of us brainstorming what could be going on. Duh, the inverter on/off was off. I turned it on and everything started working again. The next morning we went to pick up the coach and drive it the five hours to our home. The engine battery was dead at that time. We started it with the auxiliary switch and drove home without problems. We stopped a couple of times on the way home and the engine started fine. We just figured the battery had run down without the shore power inverter on and it just needed to be driven to charge the batteries. We keep it in covered storage and go up every two or three weeks to start the engine and generator for a while. It did fine until November, when the engine battery was again dead (it was a 2018 Interstate battery). We took the battery out and brought it to the interstate dealer in Texas City. They put the battery on their charger and after an hour or so, they told us the battery was “bad”. Even though we did not buy the battery from them (it was in the coach when we bought it), they replaced it with a 11/2019 battery. We hooked it up and it started right up. On 12/14 or so, we went to check the motorhome and all three batteries were again dead. We plugged in to the shore power and left it for about an hour. We never got any clicks, lights, horn...anything. I called a mobile rv tech. He said he has to have charged batteries before he can do anything. He is supposed to come out tomorrow. We took the chassis battery out ( this is the brand new 11/2019 one) home and charged it for about ten hours. Then we took it to ORielly auto parts and they put the battery on their charger. After a few hours, they called and told us the battery was “bad” and needs replacement. We went and got both six volt coach batteries and brought them to ORiellys and they told us that both of those are also bad and need replacing ( they are 2018 batteries, as well).

I will call the mobile tech this morning and see what he recommends....but i hate the thought of buying three new batteries....something is not charging the batteries and something is draining the batteries.

The only thing i can think of is that we had a new step motor and switch installed. But could that be the drain? Even with the battery disconnect switch above the entry door off?

And, of course, i have no way to know if the inverter is working. The switch is “on” but i never heard any noise. There is a little box just inside the main door that has the “fault” light lit up.

Is there something i am missing? I cannot find the model number of the inverter...it is not visible and there is no mention in our paperwork of a model number. It is a Magnum.

Can anyone think of something i am missing? I am not going to pay the rv tech for a service call if he can’t do anything without new batteries....i will buy them first....but if something is destroying our batteries, i need to fix that first.

Thanks for reading this long post!

[cavie]

Originally Posted by VincePAC

Hey, everyone. Was going to ask for ideas. We have a 2012 Bounder 35k. Have not had any problems with it until September, when the steps quit working. We brought it to our shop. They had to replace the motor. While it was there, i had them replace the switch located just inside the door because the little light in it did not work (I want everything to work!). One night while at the shop, it got into the 20’s. The coach was plugged in to shore power at the shop. They had the propane furnace running to keep it warm. We went by to check on it once the temp was above freezing again. We only had random overhead lights inside. We were all perplexed and there were three of us brainstorming what could be going on. Duh, the inverter on/off was off. I turned it on and everything started working again. The next morning we went to pick up the coach and drive it the five hours to our home. The engine battery was dead at that time. We started it with the auxiliary switch and drove home without problems. We stopped a couple of times on the way home and the engine started fine. We just figured the battery had run down without the shore power inverter on and it just needed to be driven to charge the batteries. We keep it in covered storage and go up every two or three weeks to start the engine and generator for a while. It did fine until November, when the engine battery was again dead (it was a 2018 Interstate battery). We took the battery out and brought it to the interstate dealer in Texas City. They put the battery on their charger and after an hour or so, they told us the battery was “bad”. Even though we did not buy the battery from them (it was in the coach when we bought it), they replaced it with a 11/2019 battery. We hooked it up and it started right up. On 12/14 or so, we went to check the motorhome and all three batteries were again dead. We plugged in to the shore power and left it for about an hour. We never got any clicks, lints, horn...anything. I called a mobile rv tech. He said he has to have charged batteries before he can do anything. He is supposed to come out tomorrow. We took the chassis battery out ( this is the brand new 11/2019 one) home and charged it for about ten hours. Then we took it to ORielly auto parts and they put the battery on their charger. After a few hours, they called and told us the battery was “bad” and needs replacement. We went and got both six cold coach batteries and brought the, to ORiellys and they told us that both of those are Aldo bad and need replacing ( they are 2018 batteries, as well).

I will call the mobile tech this morning and see what he recommends....but i hate the thought of buying three new batteries....something is not charging the batteries and something is draining the batteries.

The only thing i can think of is that we had a new step motor and switch installed. But could that be the drain?

And, of course, i have no way to know if the inverter is working. The switch is “on” but i never heard any noise. There is a little box just inside the main door that has the “fault” light lit up.

Is there something i am missing? I cannot find the model number of the inverter...it is not visible and there is no mention in our paperwork of a model number. It is a Magnum.

Can anyone think of something i am missing? I am not going to pay the rv tech for a service call if he can’t do anything without new batteries....i will buy them first....but if something is destroying our batteries, i need to fix that first.

Thanks for reading this long post!

Are you talking about a straight inverter or an inverter/charger combo? the switch by the steps is a battery disconnect and must be on to charge the batteries. If in storage turn it off or disconnect the batteries.

Inverter changes 12 volts to 120. Converter changes 120 to 12. Lights are 12 volt. There are paracidic draws within your coach. Stereo, CO det. control panels.

If you light says "Fault" I would suspect the latching relay in the disconnect circuit. Time for a multi-meter and some testing.

[Concord]

Hard to diagnose from an armchair, but want to rule out the possibility that your aux start solenoid is stuck linking the two sets of batteries together. If that were the case, and if the inverter was on, that could explain it.

[SavnTheWales]

I have the same motorhome and may be able to help.

You have a Magnum MM1212 inverter. It has a small remote near the door that shows charging status. There is a button in the middle of the remote that turns the inverter on and off.

The Magnum inverter draws power when in inverting mode. Even if nothing is on. It has a default sleep setting of 5 watts. The problem is that your Bounder has 3 of the 4 tv’s plugged into inverter enabled outlets. You may also have satellite dish and receiver plugged in. All of this will draw more than 5 watts so the inverter never sleeps. This means you are drawing a couple amps just sitting there.

I have fixed this a couple ways. First is to turn off inverter when you don’t need it. Second is to make sure you unplug your Wally receiver if you don’t need it on but want inverter for other reason. The Wally draws a lot because it powers the roof satellite, which likes to realign every once in awhile drawing a lot of power.

Finally I would recommend installing an AiLi power meter ($40). I bought the 350amp shunt version and put the meter just below my Magnum remote by the door. This meter will show you the voltage as well as the current draw on the batteries. Think of it like a gas gauge for your batteries. It helped me find what each thing draws for power.

Also be sure to turn off the Main and Aux switches if your coach will be unoccupied for more than a couple days. There is a lot of parasitic draws and shutting off these switches really helps.

I have been doing a lot of videos for this Bounder on my YouTube channel you might want to check out. Search for swalesutube.

[agpopp]

This thread reminds me I wanted to plug in my 35K today. I replaced all 3 batteries in the fall and wanted to give them a charge. Need to exercise the generator too.
The PO's of my rig never even knew it had an inverter. I asked them about it before heading home and that didn't know what I was talking about. At the first fill up I turned it on and wife used the wall outlet on the passenger side to charge her phone the rest of the ride.
The fact you're aware of it is a step in the right direction.