GMC Sierra III (2013-2015) 6.6l vin 8, charging circuit

AUXILIARY GENERATOR (W/ DUAL GENERATOR, AMBULANCE UPFITTER) BATTERY CURRENT SENSOR BLK WIRE BRN WIRE CHARGE IND SIG CHARGE INDICATOR COMPUTER DATA LINES SYSTEM DK GRN WIRE DRIVER INFORMATION CENTER (DIC) ENGINE COMPT NEAR FAN SHROUD) ENGINE CONTROL MODULE (ECM) (LEFT FRONT OF GENERATOR B+ GENERATOR SIG GM LAN SERIAL DATA GRY WIRE HOT AT ALL TIMES INSTRUMENT PANEL CLUSTER (IPC) IPC FUSE 43 LOGIC LOW SPEED MEGA FUSE POWER DISTRIBUTION SYSTEM RED WIRE RED/WHT WIRE RIGHT BATTERY SERIAL DATA (-) (1) TAN WIRE TAN/BLK WIRE UNDERHOOD FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) UNDERHOOD FUSE HOLDER (RIGHT SIDE OF FIREWALL) VOLT W/ DUAL GENERATOR, AMBULANCE UPFITTER WHT WIRE