Does off mean off?

It means off if the switch is between the battery post and all the wires to that post.

Many rigs have a battery disconnect switch that only isolates the converter and fuse panel from the battery, but leaves the jacks, slide, LP alarm, and stereo connected.

Generally on a batt disconnect switch esp. after market, off means off.

I however, bought a cheaper switch on Amazon a few years back that was basically a screw that tightened to connect the two plates to turn the battery 'on' and unscrewed to turn it off. If you turned it too far 'off' the plates would angle a bit and actually reconnect. I learned my lesson!

Can you pull the "key" out in one position but not the other? The position the key comes out, the battery is disconnected.

Depends on where you installed the disconnect switch in the line.

You may have other 12VDC cables hooked up to your battery terminals that may not be in the line you have the disconnect switch installed.

If you only have one cable connected to the NEGATIVE SIDE Battery Terminal going to FRAME GROUND than that would be a good spot to install the disconnect switch. Once it is OFF then the battery will not be able to power up anything... Has no path to ground to complete the circuit.

If you have several wires connected to both battery terminals then you will need to install a BLUE SEA LUG TYPE TERMINAL STRIP so that you can make all of the same terminal connections using ONE CABLE. Then your disconnect switch will OPEN UP all of the cables when it is OFF...


The DISCONNECT SWITCH should be working the same as if you physically removed the BATTERY CABLE from the battery terminal.

Guess this all makes sense...

Roy Ken

Batteries do self-discharge over time, but for a good fully-charged battery it's a fairly slow process. One source I read says it's about 4% capacity per week at 80 degrees F. The rate is temperature dependent, lower at low temperatures. You should be able to go a month or two with nothing attached without damaging the battery, but likely not a year.

Chandalen wrote:
Generally on a batt disconnect switch esp. after market, off means off.

I however, bought a cheaper switch on Amazon a few years back that was basically a screw that tightened to connect the two plates to turn the battery 'on' and unscrewed to turn it off. If you turned it too far 'off' the plates would angle a bit and actually reconnect. I learned my lesson!

This is the type I purchased, after turning it to "off" position I checked inside batt. light panel, co detector ect... everything was off so it seems to be doing the job.

Thanks for the quick replies everyone, I think the original battery had such a short life due to draining down too many times. I will reconnect after a couple weeks to see where battery life stands and figure a pattern from there.

i use one of these in the main negative line



when that comes open, its OFF
no drain except for the batteries own self discharge, which varies with type and age

MrWizard wrote:
i use one of these in the main negative line



when that comes open, its OFF
no drain except for the batteries own self discharge, which varies with type and age

Yep,exactly what I put on. Battery is brand new and fully charged,hopefully I'll get a little time between plug in's with this.

MrWizard and Tbred:

Thats the type I had, if you unscrew it too much or not enough, it will make contact.

In our Jayco Greyhawk Class C motorhome, Jayco wired the battery disconnect so that everything is off when the battery is disconnected, except the converter. I learned that the hard way when I replaced the converter. I hit the battery disconnect switch thinking that would suffice. Needless to say, I had a nice shower of sparks when both negative and positive wires hit the converter chassis while putting the new converter in place of the old one. Not sure if it should be like that or not, but I left it that way.

-Michael