Hi folks
I have been having some odd issues with my MACH4 recently and I am not a computer person so I was wondering if someone could just point me in a good direction to diagnose this.
I have been losing my work zero's and I have to go back a dereference the machine. So there have been times when all my lights on each axis are green and then it loses them and they turn red. Sometimes when I rehome the machine, it throughs me off on my work coordinance and it ruins my part.
Sometimes when I home the machine it ignores my home switch and keeps going and I have to estop the machine.
I am just wondering if the ESS board would contribute to this OR should I be looking more at the main computer I use to run mach?

More likely ESS board of BoB I would think - bad contact?

Thank you for the input. That gives me a place to try. Possibly in the ribbon cables but I might try a new ESS to see what happens. 

An expensive trouble-shooting technique unless you happen to have a spare!

Yes I get it but this is really intermittent, and I do not want to spend a ton of time chasing my tail.
I came in this morning and had left it on last night. I could move the gantry no issues, but I could not go to work zero nor could I use MDI to move it and for some reason it was getting a G53 error. Yesterday I homed it and it homed x & z but failed to move y and said the function was complete. I think you could be correct that the ESS might be failing possibly the hotter it gets? Kinda at a loss and thought I would try this first.

electronics generally is very reliable, it's the connections that go.

Well brother I believe you were partly right. Looks like I had a little connection issue with the Z+ but I have a question for you. While fixing this connection the light in the diagnostics tab was on (good) but then the ESS lost communication for some reason (does this more and more). So, for the heck of it I put a new Cat5 cable in and double checked all the connections on the ESS. The normal warning came up on the computer screen asking if I want to try and reconnect and I said yes. Well, the message went away, and I believe it regained connection as the warning never came back BUT I could not get the Z+ light in the diagnostic tab to go out AND I could not get any other lights to come on (X/Y Switches). I also made a couple of changes in the Config screen just for the heck of it (Z+ changed to ACTIVE LOW) and it said it saved but when you get out of the inputs config page and then go back in it never saved it. After all this I rebooted the panel and MACH4 and everything worked again as it should. Does any of this garb I just told you sound like the ESS might be bad or going bad?
I am just not smart enough to understand the difference between what the ESS does and if it actually stores data or could possibly cause these kinds of issues? I find it odd that rebooting the panel and Mach would make everything work again possibly eliminating the PC?
Thanks for your input!!

I don't know about Mach 4 but m3 does get in funny states sometimes and can only be rescued by a reboot.

Great that is what I wanted to hear. I used to run 3 and this was a smaller issue than 4.