View attachment 1714957848
I assume this is the wiring. First check would be to use multi-meter to verify ground connection and 12V power. You can use meter on AC volts, to see what is happening on tach wire, it should vary some with RPM.
Looks like what I did? As far as signal check is concerned, MSD says check the gray wire with engine at idle. Use a volt meter set on DC and voltage in the gray line should be about 5v engine running at idle. Maybe I will do that today. I guess where I jumpered all the white ground wires from gauge to gauge maybe I have a ground issue. So I may just make up a pigtail and run it directly from the gauge to a separate good ground to see if that would do anything?
