Hello,
Yesterday I was helping a friend replace his alternator in a MkII. He was going from a unit with a built-in voltage regulator to a two-piece setup (alternator + external regulator).
It seems to work - 12V when not running, then the voltage rises when the car is running and tops out at 13.8V when revved.
One problem... There is a blue wire coming from the tachometer that was previously hooked to the old alternator. This appears to be the "Gen" light that would come on to indicate that the alternator was not charging. Any clues on where this would go? We tried the stator and field lugs on the alternator, but neither appeared to work (the light did not come on when the ignition was on but not running).
Thanks!
Charles