Whirlpool Refrigerator SxS Evaporator fan working in eratically

Hello All,

My side by side whirlpool model ED27DQBN00 stop cooling one day
and both the fridge and freezer lights stop working even after I change the light bulb. After lot of searching and checking I find that the compressor is working (it is still running and cold) but the evaporator fan only blow when the doors are opened (the light switches are on) and the temperature control is turn off. I discussed my problem with other online experts and one suggested that I might have a short or stray somewhere.
I looked for the wiring diagram everywhere on/in/underneath/behind the grille but could not find it. I might have lost it during moving sometime ago. I wonder if anyone have the same problems and can help me out. Any ideas is greatly appreciated. Does any one has the tech sheet for this model?

Thanks
L.D