[Gasoline Fumes]

Grounding the alternator's C terminal will put the alternator in the 12.5v low output mode. I keep mine there most of the time. I have disconnected the wire to the ECU and ground the C terminal manually through a resistor. The resistor might not be necessary, but I put it there anyway. I might've used a 100 ohm, I'm not sure. The alternator won't be totally off if you do this, but it won't be working as hard either. You'll want a voltmeter in the car. Running too high of an electrical load in this mode will drain the battery.