VALVE GP-PUMP CONTROL 4557949 - Caterpillar

Harness Wire Identification
Caterpillar identifies different wires with 11 different solid colors. Table 1 lists the color codes of the wiring.
Table 1
Color Codes for Wiring    
Code     Color    
BK     Black    
BR     Brown    
BU     Blue    
GN     Green    
GY     Gray    
OR     Orange    
PK     Pink    
PU     Purple    
RD     Red    
WH     White    
YL     Yellow    In addition to the color, the entire length of each wire is stamped with a specific circuit number that is repeated on every 25 mm (1 inch) of the wire. The actual wires are identified on the schematic.For example, a code of J011-RD on the schematic identifies a red wire that is stamped with the circuit number J011. This particular wire is the engine harness wire for the primary signal of the transformer in the number one cylinder. For all Caterpillar engine harnesses with electronic ignition systems, the code of J011-RD identifies the wire for the primary signal of the transformer in the number one cylinder.The schematic also identifies the size of the wire. The size or gauge of the wire is called the American Wire Gauge (AWG). Unless the schematic specifies a different size, you may assume that the wire is 16 AWG.