Battery Charging

[pendergastjm]

I know this has been discussed, and I believe I have sorted through all the available information, so please pardon my newbie question on Battery Charging. I have a 2018 TB Interstate Grand Tour EXT, which I believe is on a 2017 chassis. I live in Wisconsin, so will be storing the AI in a rented storage unit that is not heated, but has 120v available. If I plug the AI into this 120v outlet, but do not turn on the master switch that is by the entry screen door, the chassis and house batteries Will NOT charge, correct? If so, does putting a charger on the chassis battery via the terminals under the from hood, charge either battery? The reason I am asking is after a couple of weeks with the AI plugged in, but without a charger on it, the chassis battery was showing "red" on the monitor panel. Once I threw a charger on the chassis battery, (again via terminals under front hood), the chassis battery started to come back up to a better voltage. Thanks for any input you can give!

[nvestysly]

I am not an expert on your van but our 2010 Interstate had a similar problem - that is, with the battery switch in the off position the house (motorhome) batteries would discharge in a week or so. Our van has a different switch but I realized it did not disconnect everything - there was a 0.2A draw so it was only a matter of days to discharge the batteries.

To solve the problem, we installed a manual on/off battery switch. We put this on the positive lead coming from the battery. Now, when this switch is off the entire 12V system is off. You may want to consider a similar solution.

Regarding charging the house batteries from the underhood jump starter contacts - it may work, but I thought the ignition switch would have to be turned on in order to activate the circuit from under the hood back to the house batteries. Again, I'm not an expert.

[Schmitte]

Welcome to the group

I don’t have your model but what you describe sounds like something reported here and was related to either the stock AI battery isolator and /or fusion radio drain

AFAIK, the battery should still receive charge when the Main Disc switch by the door is off. At least that’s how my 2015 is wired

[ScottP]

Originally Posted by Schmitte

Welcome to the group

I don’t have your model but what you describe sounds like something reported here and was related to either the stock AI battery isolator and /or fusion radio drain

AFAIK, the battery should still receive charge when the Main Disc switch by the door is off. At least that’s how my 2015 is wired

2014-2017 units:

I’m pretty sure the “master switch power turned off “ yet charging whilst plugged into AC method changed after the 2017 unit.


For a 2018 unit:

I believe your master switch must be in the “on” position whilst plugged into AC service, to charge the coach batteries.


[emoji6]

[Titus]

I have installed a second battery switch to cut off what power the factory-installed cut off switch does not control. With both switches off I believe that I can safely over-winter with the coach batteries in place. (I do not have a Fusion radio.) But given that I can pull the coach batteries in 15 minutes time, that is what I do. Then when I get to the storage place I disconnect the chassis batter using the plug by the accelerator pedal. Instructions for my Blue Sky solar controller say that I can disconnect batteries with the panels being powered. But to be safe (again) I always disconnect coach batteries early or late in the day - when solar charging is minimal. There is probably a bit (or maybe a lot) of overkill in my wintering preps, but much easier to spend some time up from than fix things later.

[Rusted]

Originally Posted by nvestysly

I am not an expert on your van but our 2010 Interstate had a similar problem - that is, with the battery switch in the off position the house (motorhome) batteries would discharge in a week or so. Our van has a different switch but I realized it did not disconnect everything - there was a 0.2A draw so it was only a matter of days to discharge the batteries.

To solve the problem, we installed a manual on/off battery switch. We put this on the positive lead coming from the battery. Now, when this switch is off the entire 12V system is off. You may want to consider a similar solution.

Regarding charging the house batteries from the underhood jump starter contacts - it may work, but I thought the ignition switch would have to be turned on in order to activate the circuit from under the hood back to the house batteries. Again, I'm not an expert.

Hello
Have a 2013 AI wondering where did you locate the switch?

[nvestysly]

Ours is the twin bed model. The batteries are under the road side bed inside a metal box. There was a little bit of room just outside the box but still under the bed. That’s where I mounted the new disconnect switch.

There were three positive wires running from the positive post that fed through the metal battery box. I removed those three wires and attached them to the output of the switch. Then installed a single 2 gage wire from the positive feed through to the input side of the switch.

This is not the best picture but you can see one wire into the switch and three wires out.

[Beemerman]

Pendergast & co.......
On my 2019 GT EXT that I just traded (for ‘20 IS19)..... I always kept 20A shore power plugged in with small red “Batt Master” sw (near screen door) OFF. Never had any voltage issues...... from my limited smarts on these contraptions, there are unique differences between model years.......thoughts ?

[pendergastjm]

Originally Posted by Beemerman

Pendergast & co.......
On my 2019 GT EXT that I just traded (for ‘20 IS19)..... I always kept 20A shore power plugged in with small red “Batt Master” sw (near screen door) OFF. Never had any voltage issues...... from my limited smarts on these contraptions, there are unique differences between model years.......thoughts ?

What you describe is what I was doing. However the chassis battery was losing power after about a week. I am now keeping a trickle charger on the chassis battery and that seems to keep the voltage up. Thanks for your input!