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The controller board LED could tell you a lot about what the problem is.
The controller board LED can only be checked if you remove the cover from the machine, then power it On with the cover off. The controller board is located very near the motor, sometimes under the 'motor hood'.
What pattern do you observe on the controller board LED? On steadily, or flashing? if flashing, flashing in groups of flashes, or some pattern, etc.?
As for the PWM LED flashing... that means power-to-motor is in doubt.
This could mean several issues, but observing the controller board LED's flash pattern could tell much more about what the exact problem might be.
At a guess, and at this point, something could be severely enough wrong with the circuitry that repairs might well be necessary. For instance, the power supply part could have a defect and not be supplying power to the motor... this is not common, and not too likely. Or, the wiring leading to the controller board, or from controller board to motor, might be loose. Or several other things might be wrong, depending upon whether you have moved the Proform machine lately, how old it is, whether it has been stored in either dirty or cold or hot places, or used in a moderately cool place (below 55 degrees F. or so, approximately), etc.
Let me know more, and I will instruct you further toward a solution to this problem.