OK, need the board's electrical guru's help on this one. I've got alternator issues, and I'm stumped. Bottom line - I'm not getting any charge to the battery.

First data point: Had my engine out a while back, and when it was reinstalled I switched the alternator D+ (red) and D- (brown) wires at the plug into the relay board. Gotta love red/green colorblindness... Figured that out and switched 'em back, but not before running it for a while like that. Once fixed, still no charge.

I've tried 3 (so far) new regulators with no effect. Still no charge. I can't believe all 3 of them are bad.

I've run the tests described here and here, and the alternator seems to pass fine. 14 - 16 volts during the test, but reinstall the regulator - no charge.

I've ordered one of Bowlsby's alternator harnesses, thinking that perhaps one of the wires is shorting between the relay board and the alternator. Figured it couldn't hurt anyway, as that's the only engine bay wiring I didn't replace in the course of my Megasquirt conversion.

Anyone have any ideas? This is really getting frustrating...

Unfortunately, it probably is the alternator. It may produce 12 volts, but not enough amps to actually operate anything. BTDT. I got a non-bosch alternator (after the dang rebuilt things kept keeling over) from a place near DC called Arlington Armeture- they had alternators or generators for almost every car ever.