This previous post may be of help to you.
I believe what you have is a DC voltage variable speed board controlled setup now that I see the pictures. You will probably spend more than 500.00 to 600.00 on parts. There is a expensive electronic tool that is made just to check/test those items.
It is a proven fact that you will not save energy with that setup because when it goes bad you will spend more than you saved for new parts.
I suggest calling a pro HVAC company that has the proper tools/meters etc to fix it correctly and at the minimum of expense for parts.
OR
Do the smart thing. Rip out all blower controls and motor.
Replace with a convential 3 or 4 speed motor and wire it up.
Been there done that and it is a bunch cheaper.
Here is some not the same brand information about variable speed.
http://www.nordyne.com/Literature/349c.pdf Evergreen ECM Replacement Motors | GE ECM by Regal Beloit | theDealerToolbox.com