|Hello again. Tonight, I decided, since I had an hour to kill, to try to figure out why Ms. Jenavieve's tach hasn't worked since I got her. So, armed with the foldout wiring diagram from the owner's handbook, I started poking around (yes, I was finally introduced to the Lotus position). I pulled the tach out and did some voltage testing on the wires... and they mostly seemed to test the way I expected them to (white and green were each 12v when the ignition switch was turned on, and the body of the tach was definitely grounded).
However, the white/slate (the one that runs from the tach to the ballast resistor) was only giving me about 0.7v. From what I've been reading, that should be more like 9 to 10v. Granted, I didn't have the engine running when I ran the tests, so maybe I am misunderstanding how the connection from the solenoid fits into the whole equation, but it appeared to me that I should have gotten some sort of backfeed through the ballast resistor to the white/slate wire connector. Or is that connection only "hot" when the solenoid is actually engaged (i.e. during starting)? Now that I think about it, that would make more sense...
Anyway, my question: what should the resistance of the ballast resistor be? I haven't found any reference to it anywhere. Should be easy enough to test if I knew what the resistance should be, and just trying to narrow down possibilities before I assume it's a faulty tach.
I had previously attempted a test by pulling the white/slate wire off the ballast resistor and trying to start her... and she would cough once and die, so I assume the resistor is doing "something". Just not sure it's doing what it's supposed to.