How to Wire a Chevy Alternator | It Still Runs How to Wire a Chevy Alternator by Kevin Krause . The GM alternator used in all Chevrolet models is easy to install, as it is connected using only a few wires. The alternator converts the engine's mechanical rotations into an electrical current using a pulley-and-belt system. This current is fed to the car's battery, charging it for later use. Alternator and charging issues on an '85 - The 1947 Aug 16, 2008Re: Alternator and charging issues on an '85 After seeing the wiring diagram for bulb type clusters, I was wondering the same thing about a burned out bulb. If the brown wire needs switched voltage to make the alternator work and it gets it THROUGH a bulb, would make sense that if the bulb burns out that the alternator wouldn't charge.