disconnect them one at a time and ohm them out. check the IOM for a temperature/resistance chart and compare the meter reading verses the chart resistance for the current temperature at the sensor location. also check dc volts at the sensor connection to the processor. There should be (usually 5vdc to ground at one of the two connections) some dc voltage at the sensor input. If there is no voltage, the processor may be defective.
Thanks, I picked up the service manual this morning. Heading out there now. I was getting strange voltage readings on f1 and f2 also. The voltage was jumping all over from 1 to 16VDC, It did this with the wire connected and disconnected. I'm pretty sure all the thermistors are the same