Tach output for 2000 NB
 

For some reason I never got the tach output working with my old build. Thought I'd get that sorted now the car is back up.

So I remember it being different than the NAs, but I can't remember how, so can anyone point me to the right thread? I tried searching around for the past bit and can't find anything.

Thanks

The dashboard tach on an NB is fed by the ECU, similar to a '95.5 or later NA.

On an '00, it's a green / orange wire at position 2K of the ECU. Set up a circuit in the MS to give it a 0-12v squarewave with one pulse per ignition event.

So a two channel optoisolator fed from the ignition signals on the MS passing 12V through a 10K resistor, or thereabouts?

you just need one pn2222 transistor a 10K and a 1K resistor.

https://www.miataturbo.net/attachmen...ine=1311702662

Dang, duh.

Thanks, I'll get in there tonight and get that gauge finally working. You know I just lived with it for 6 months before the car went down that I didn't work...

Appreciate it guys.