Ignition switch
Power supply from the ignition switch. There are three power supplies: 15/1, 15/2 and 75.
Position 0 = Off.
Position 1 = Radio position.
Position 2 = On.
Position 3 = Engine start.
Incorrect position 0 = Impermissible combination of input signals.
Incorrect position 2 = Impermissible combination of input signals.