evaporator fan not working

Tested the white and red on J2 and read 13vdc. Replaced the fan and the unit went into defrost in the mean time. I unplugged the unit and hoped to skip the defrost and the unit begun to start a cooling cycle. The evaporator fan did not come on after about 25 minutes. I retested the J2 at the red and white, and reading was 13vdc. What am I missing?
The overheat T-stat was swelled and needs replaced. Does that affect the starting of the evaporator motor. Does the evaporator motor need the full frost pattern have to reach the over heat stat and thermistor before it senses and turns on the fan?