Hi there, my 126 rev C , serial 32896 has developed what appears to be a fault after several years of flawless operation, there have been no changes to hardware /wireing/layout etc, occurred in the middle of a cut.
The E-Stop led is now permanently lit even with everything disconnected apart from just a jumper across e-stop and adjacent ground. The connected EES was reporting the Estop to mach4 in diagnostics.
I've now pulled the board and disconnected the ESS and pmdx-107.
its now on my workbench free standing with the only the jumper still across estop and all dip switches set to ON, (normally off,on,on,on,on,on,on,off) JP1 =pin1 , JP2=multimode, JP3=off, JP4=off, JP5=off
Estop still lit and the L78M regulator at U6 gets too hot to touch within a few seconds. There is the beginning of heat discoloration around the thermal vias underneath it.
The test button lights the test led while pushed and then immediately goes off on release, no other change to any other leds, estop and power remain lit, enable doesn't light.
No error codes. Immediately upon power up status and steps leds flash once followed by a flash from enable, after that they remain off. estop led does one very break pulse, I assume scan, then remains lit with power.
It seems something has gone closed circuit across whatever is downstream of U6 or maybe even U6 itself, maybe.
Any thoughts? any chance of a circuit diagram or diagnostic voltages and probe points? I'm in New Zealand so return for service will be extremely inconvenient and costly, I have a rework station and surface mount experience.
Cheers in advance.
Ron
