Found information on youtube as to how to diagnose it. was fairly easy once I had the information. I replaced the inverter board. I confirmed that it was getting 120 ac line voltage, also confirmed that is was getting the proper control voltage of 4 to 6 volts dc from the the motherboard. then I verified that the compressor windings had the proper resistance of approx 7 ohms on all 3 windings. It was basically the process of elimination. However everybody I talked to said is was probably the motherboard. It always pays to diagnose it. Guessing could get costly. The part was the the exact OEM replacement part, and it was shipped quickly as promised. Fridge works awesome. Should I need the Motherboard down the road, I will be ordering it from appliance parts pros. Thanks again John.