Simple Power Mode

Power mode signal may be as simple as a B+ input wired to a particular ignition switch contact. If this is also B+ supply to a module/device, module/device will only operate with ignition contact closed to B+. An example of this is the starter relay when it is wired directly to CRANK/START contact of ignition switch. When CRANK/START contacts are closed, starter relay is energized and provides a current source to starter and starter solenoid. When ignition switch leaves CRANK/START position, switch contacts open and starter relay is de-energized. This removes current source from starter and solenoid and starter operation stops.