I need help please. 08 F-350 diesel. 2 batteries, 2 alternators. Battery light lit. check cold after sitting 30 hours, both batteries at 12.3 V, start engine and recheck, both batteries at 13.2 V. Drive to my shop pull and clean all connectors on both batteries, restart and check. Now both batteries at 14.2 V, Battery light still on. I have not found a post with two alternators and two batteries. any suggestions on what to look for next???