[lukemckenzie]

I have a Fadal 4020 with the 88HS which will not has been having problems for a while.
At first it would simply drop out from time to time. Then it started stopping mid program as though the code ended.
Most recently it has started doing all kinds of funny things, going left when it should of gone right, not starting when the green cnc power button is pushed or when in the ENTER NEXT COMMAND screen it will continuously bring up random numbers.
I have noticed that often the little red light on the 1030 board is not flashing or not on when these problems occur so I put the machine in diagnostic mode and ran a heap of tests with no faults. That said when running the tests I noticed that the successful test counter would count 1,2,3,A,B,C,D,E,F,10 etc.
It has gotten to the point where I often cant even get the CNC to power up at all and I need advice on what could be the cause of these problems.

[DareBee]

The 1st 2 things I would check is the PC type power supply (the fan seizes and they burn out) and pull all the control boards (the slot connectors can get corrosion and not be contacting).

[warrenb]

What do you mean won't power on? There is no power to anything when you throw the main switch? Or when you hold in the green button?

I always had a hell of a time at the main transformer. The model I have has so many wires trying to plug in to their connectors that a wire would slip out occasionally.