Yes, alternators produce AC voltage, but the regulator that is now built into the alternator turns it into DC before it goes anywhere.
No, the signal from the crank sensor is an interrupted DC signal on/off/on/off/on/off/etc.
The test light should flash when the alligator clip is placed on a constant power source and the probe is touched to the negative on the coil.
The relay is simply a high current switch. One set of terminals is the switch, one is where power is applied, the other (used connector) is where the load is. There is also a terminal, 87a, that a load that needs power when the switch is not energized would go. If there is an anti-theft notification, it's from an anti-theft system, not the starter relay.
Saturday, February 4th, 2012 AT 4:01 AM