Our machine seized up while running a job.
Controller power light is blinking and fan turns on intermittently with it.
Machine is very hard to move by hand, even with the power off.
When I disconnected all the power plugs from the motors, its suddenly free again. Power is disconnected at all times.
Is my controller fried? Did it take the motors with it?
1 - Possible
2 - Unlikely
Question: does the controller have a source of power inside (battery?) I find it strange that with the controller power cable disconnected, the motors are still engaged. With the motor cables disconnected, they are free to move again.
No there is no battery.
Sounds like the controller board might be toast, a stepper will “lock” if one or both of the wire pair have contact - even a unconnected stepper in your hand. (Magnetic properties)