Just got sent to figure out why the #1 fuse keeps blowing on a 2004 3500 cab chassis. They suspected the ficm is bad. I pulled both connectors on the ficm and still blows fuse. I read that the harness can short to the alt. bracket so I looked and sure enough there were arc marks on the bracket. I pulled the covering off of the harness and found some repair had been made. I now suspect the repair because there is a large wire (maybe 12 GA.) soldered to a small (18-20GA.) wire leading to the ficm. I haven't been able to speak with the person who did this and no wires appear burnt. I need to see a schematic with color codes to just see if this is repaired correctly so I can look for the short further upstream. Anybody have a schematic that could enlighten me. ? TIA
