This SAE Recommended Practice covers the requirements for all marine inboard engine wiring, wiring assemblies, wiring components, and wiring connectors connected to microprocessors associated with the operation of the propulsion system. The purpose of this document is to insure that electrical and electronic wiring and wiring components used in a marine propulsion system meet the necessary safety and performance requirements based upon the marine mechanical and electrical environment. The recommendations include methods that may be employed by manufacturers to minimize the possibility that engine wiring may be a source of ignition of explosive or flammable vapors and provide manufacturers installing engine electrical systems sufficient information to design and develop engine wiring harnesses for marine usage.