Wiring battery combiner into 7 pin harness
Hey everyone. I've got my truck camper permanently on my 1998 GMC K3500 and unfortunately cannot easily access the 7pin harness to unplug when it is off the truck. I quickly realized that with it full...
Forum Discussion
BurbMan wrote:
You do want some type of battery isolator like this one so that when the truck is running you'll charge the camper battery. Pulling the stud 1 fuse will prevent the camper from draining the truck battery but will also prevent the truck battery frm charging the camper battery.
The isolator can be anywhere between the two batteries, either under the hood, under the the bed or in the camper. My 2002 Lance had one under the sink where the 7-pin cord came inside.
Isolator, expensive overkill plus the isolator will have at least .7V voltage drop which pretty much effectively kills your charging potential to the TC battery when engine is running.
Instead, opt for a $8 12V relay which the coil is connected to the ignition keyed source which is powered only when engine is running.
Common 12V relays are the "Bosch" cube style which are typically 30/40A which would be enough to cover the charge fuse.
For overkill they do make a 70A Bosch style relay..
