Answer Hello Craig, Error F-133 is for an Open temperature sensor (RTD). The tech sheet say to do the following: (1) Check all heater, sensor, and wire harness connectors. Make sure they are tight and secure. Check heater ribbon for possible damage. (2) Remove sensor connector from the board and measure RTD resistance. Should read from 1030-1150 Ohms (46°F-102°F.) If it does not, replace the heater and recalibrate inductive sensors. (3) If fault persists, replace main board and recalibrate inductive sensors. Read More... Answered by AppliancePartsPros.com | Thursday, June 19, 2014