GMC Cab & Chassis Sierra 3500 (2004-2007) 8.1l vin g, transfer case circuit, selectable

2-HI IND 4 HI 4 LO 4-HI IND 4-LO IND 4-LO IND 4-HI IND AXLE SW SIG BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE CLASS II DATA AXLE CTRL CONTROL MODULE DIESEL: ENGINE CONTROL MODULE CTRL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) DIESEL (ECM) DK GRN WIRE DK GRN/WHT WIRE ENCODER ENCODER LOW GROUND ENCODER SIG FRONT AXLE ACTUATOR (ON FRONT AXLE) FT SHAFT LO FT SHAFT HI FUSE GAS (PCM) GROUND BATTERY MOTOR CTRL A MOTOR CTRL B GRY WIRE GRY/BLK WIRE HOT AT ALL TIMES HOT IN HOT IN RUN OR START I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) SEO IGN FUSE I/P RELAY BLOCK (UNDER LEFT SIDE OF DASH) IGN E FUSE ILLUMINATION INSTRUMENT PANEL CLUSTER LAMP LOCK SOL CTRL 2-HI IND NEUTRAL IND LOGIC LT BLU WIRE LT GRN/BLK WIRE NEUTRAL IND ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE RED WIRE RR SHAFT HI RR SHAFT LO RUN WIRE SHIFT MOTOR SPLICE PACK TAN/BLK WIRE TRANSFER CASE ENCODER MOTOR (LEFT SIDE OF TRANSFER CASE) TRANSFER CASE SHIFT CONTROL MODULE (BEHIND HEADLAMP SWITCH) TRANSFER CASE SHIFT CONTROL SWITCH TRANSMISSION SYSTEM TREC FUSE UNDERHOOD FUSE BLOCK (LEFT SIDE OF ENGINE COMPT)