The factory battery is connected as usual, and then a separate capable powers the 2nd battery's positive terminal from the main battery's positive terminal (which comes from the alternator). The isolator ensures the two batteries are only connected when there is sufficient voltage coming from the main battery. It is a pretty easy install that requires minimal modification to the factory wiring or electronics.Please eloaborate on a ISOLATOR for the GM/Chevy trucks. I have a 2003 Duramax, and before that a 1985 F150 4x4 that i added a isolated dual battery system that allowed me to jump the starter battery from the aux. battery. There has been 2 times that my batterys went flat in my Silverado, along with a slow starter,which only manifested itself at that point.
I was not aware (electrical newbie) that a dual battery isolator system was possible without some kind of elaborate rewire! So please do a follow up on what was involved...thx