ok so like over 6 months ago when my 914 wasn't running i redid all the connections at the coil, put in a new relay board, and rewired some wires that needed it (along with diagnosing and fixing the starting issue). Ever since then my tach hasn't been working. I checked the purple/black wire that goes from the coil to the relay board and it seems ok (though i haven't tested it yet). I was wondering what other issues could cause the tach to go out. I really don't want to get a new one or get this one rebuilt unless i have to.

Power, ground, and signal. That's what the tach sees. Are they all good? Especially the ground? Is the black/purple wire connected from end to end?

--DD