Help. For some reason all the sudden my touch plate probe is not providing a signal. (in both Mach3 and Mach4)  I conducted an auto Z function with the plate with no problem. Then tried to auto z again a couple minutes later and there is no signal to the probe all the sudden. Very strange, as nothing changed and it all the sudden stopped working.  I can't get it to go active.

Hello.
Mr donleedman.

Did you directly check with a tester whether the output signal from the Probe was generated?
If there is an output signal from Probe, the problem seems to be difficult.
First of all, why don't you check it with a tester?
If you have already confirmed the hot water, please forgive me.

Hello
My probe just stopped working to my surprise and just kept moving into the spoil board.
I have a simple three axis wood router.
Using CNC4PC C94 breakout board, UC300ETH controller and Mach 4
I was installing a pendant MPG2, which never worked as well.  But when I started a new project the probe stopped working.
I have reinstalled all of my software several times using new and old builds and cannot get a touch signal out of the board.
I do have continuity in the probe circuit.

1. Check the probe output signal.
2. Check the signal from the break board.
3. Check the output signal of the board.
Check all of the above with a tester.
If everything is normal, I think there is a serious problem.

I have tested the probe circuit well it was running. There seems to be no voltage going through.
Tried moving to another input port and the same result. 
I have reinstalled Mach4 several times trying different builds.

It would be best to find out what is faulty and replace the faulty one.