West Coast Green Highway: Electric Vehicle Signs Highway Signs: To direct motorists to publicly accessible electric vehicle charging stations, west coast states are using the Alternate Electric Vehicle Charging Symbol sign (D9-11b Alternate) along the highways. The signs are posted at the interchange or intersection nearest to the DC fast charging facility with follow-through signs on the off ramps. Master Automotive Wiring Diagrams and Electrical Symbols Automotive electrical diagrams provide symbols that represent circuit component functions. For example, a few basic symbols common to electrical schematics are shown as: (1) Switch, (2) Battery, (3) Resistor and (4) Ground. Note the switch symbol displays an open or closed circuit path, which is what an actual switch performs.