The battery provides the entire electrical current to the vehicle before the vehicle is started, including the fuel and ignition systems, which are responsible for starting the vehicle. The starter uses a small amount of power from the battery to rotate the flywheel, which turns the crankshaft, moving the pistons. Car Electrical System Repair Services. Your car’s electrical system is a complex network that requires specialized diagnostic equipment for comprehensive servicing. A technician can access your vehicle’s data with diagnostics and identify the exact cause of any electrical problems.