Purpose And Scope

This Recommended Practice is an endorsement of SAE J2191, "Recommended Practice for Identification of Standardized Truck and Tractor Electrical Circuits." SAE J2191 defines a method for implementing circuit identification for the circuits of the power and signal distribution systems on Class 8 vehicles. It describes a supplemental circuit identifier that shall be used in conjunction with the original equipment manufacturer's (OEM) primary circuit identification as used in wire harnesses, but does not include electrical or electronic devices which have "pigtails."