E350 reconfiguring Battery cables
I have an AMP light on since a "mechanic" changed the Alternator on my van. He also caused a few wonderfully time consuming & painfull problems I have already dealt with. I now want to get two full size batteries on the truck instead of the one large and one skinny (pass side). I fabricated a bracket and mounted the second battery on the frame rail as was done in the later model vans. I ran a very heavy Pos cable from both batts to the starter. This is the same way it was done at the factory except the cable is coming from two locations instead of a single one-w-the 2nd battery Pos term "spliced" into the cable-w-a special post connector b4 going to the starter. My question is about the charging wire that goes first to the starter relay on the radiator core support and then to the left batt (which goes to the starter & frame mounted battery). I am thinking it would be better to go from the alternator-w-another wire of maybe #6AWG to the frame battery. It seems like the original setup would cause the right side battery to suck the juice from the alternator if it needed it and leave the leftovers for the other battery. I now have 2 850CCA batts but for some reason the AMP light stays on whenever the truck is on. This original design just does not sit right with me. BTW-I have a marine type battery disconnect setup so there is no danger of hitting a hot to ground while wrenching.