Dedicated Starter Battery / Dual Battery?

[KTruck75]

Can somehow help me to understand exactly how the OEM Auxiliary / Camper dual battery configuration is designed to work? parshal's thread http://www.gm-trucks...howtopic=102220 is what I'm looking to do.

 

I have a 2007 Suburban and my wife is constantly draining the battery. Between taking the kids to and picking them up from school (can't have the motor running in line) and her dance studio, she's in and out of the car all the time without starting it. Lights stay on, the radio stays on, dvd player stays on, etc until they timeout or until you open a door. This can easily drain the battery. To help some, I turned off approach and exit lighting as we have no need for all lights to come on and stay on that long. We still occasionally drain the battery and need a jump start.

 

From the OEM schematics, diagrams and photos, it looks to me like the main battery continues to provide power to the entire truck when not running while the Auxiliary battery just sits there doing nothing unless it's powering a camper or trailer attached or anything else attached to the Aux posts in front of the fuse box (probably need to remove the main harness from the Aux post if you have it hooked up or you'll drain both batteries together).

 

Wouldn't you want the main battery isolated when off therefore only supplying power to the starter? What if you leave your headlights on along with the dvd player, etc and you drain the main battery all while you've also been running other things off the auxiliary battery such as a camper you are setting up.

 

Am I missing something? Am I misinterpreting how the OEM Aux Battery is supposed to work? Looks to me like the Aux battery is just there to help the main battery during start up and during run but when turned off it's just for powering add-on auxiliary items.

 

Thanks!

Kevin