GMC Forward Control P3500 (1985-1999) Anti-lock brake circuits, commercial chassis

1-3 FUSE 9 12 2 DATA LINK CONNECTOR (BELOW DASH, NEAR STEERING COLUMN) PPL ABS IND. BATTERY GROUND BLK (OR BLK/WHT) WIRE BLK WIRE BRAKE IND BRAKE PRESSURE DIFFERENTIAL SWITCH (INTERNAL TO ELECTRONIC BRAKE CONTROL MODULE) BRN WIRE DIESEL DIESEL: ENGINE HARN, 32 CM FROM BREAKOUT TO BATTERY JUNCTION BLOCK) DIODE NETWORK (ON I/P HARNESS, BODY BUILDER INSTALLED) DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (BELOW RADIATOR, ON LOWER CROSSMEMBER) FUSE LINK (IN BATTERY JUNCTION BLOCK, AT LEFT REAR OF ENGINE COMPT) GAS GAS DIESEL GAUGES FUSE 8 HOT AT ALL TIMES HOT IN RUN HOT IN RUN AND START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) IGNITION ABS LAMP CONTROL BRAKE SW INPUT INSTRUMENT CLUSTER LEFT FRONT WHEEL SPEED SENSOR LT BLU WIRE LT GRN WIRE NCA WIRE PNK WIRE PPL PPL PPL 1807 680 RED WIRE RIGHT FRONT WHEEL SPEED SENSOR SENSOR LOW SENSOR LOW SENSOR HIGH SENSOR HIGH 873 833 STOPLAMPS SWITCH (AT BRAKE PEDAL SUPPORT) TAN WIRE TAN/WHT WIRE VEHICLE SPEED SENSOR CALIBRATOR (LEFT SIDE OF DRIVER'S ISLAND ON RELAY BRACKET) WARNINGS SYSTEM YEL WIRE YEL/BLK WIRE