This all started a couple weeks ago with a relatively warm day.

My 1993 VMC20 tends to overheat when the temperature approaches 80°. It will restart the computer. I forget what the error message would say. I would just open the back side cabinet and let it cool off for half an hour or so.

On this particular day, I ran it with the cabinet open and a fan blowing into it. Toward the end of the day, it stalled and gave me Error #16 Resolver fault. I checked the resolver and was getting no voltage. I found that the motor bearings were shot, so I ordered a reman motor with reman resolver on it. Installed it today, but got a strange squeal from the amplifier area of the cabinet and an error message showing an x-axis amplifier fault. I reset it over and over and over to see if it was just the process of the mill adjusting to the new motor. The message kept coming back. The 1st and 3rd LEDs light up on the amp board too.

So I switched the x and y axis amplifiers as suggested by tech support. The error stayed on the x-axis and the LEDs lit up the same. I switched them back.

Then I pulled the new resolver and installed it on the old motor. Same error.

Then I pulled a resolver from my VMC 4020 and installed it on the old motor. Same error.

I should note that it is possible sometimes to jog the x-axis motor slightly. It seems to begin to work if I leave the mill on before disengaging the emergency stop. Sometimes it will not throw the error right away. I jog it about .050" with the pendant wheel and then it throws the same x-axis amplifier fault code.

Stumped and frustrated. (chair)