'ello, all -
Decided to bring this to the experts, because between this dryer and myself, one of us is going to die by the end of the month if this doesn't get figured out. Besides... everyone likes a puzzle, right?
SO - have a Maytag Neptune MDE-5500AYW dryer that I bought new as part of a pair way back before the turn of the century. Both worked flawlessly, until I lost the washer to a tragic incident of the motor speed control board burning out. The dryer still continued to work beautifully until this past holiday, at which point suddenly the sensor dry decided to go wonky on it.
Let me say first, that timed dry works just fine - no issues whatsoever. Based on this, I have a tendency to believe that the thermal fuses, cycling thermostat and hi-limit thermostat are okay. Also, the internal workings of the dryer as well as the ducting throughout are completely spotless so airflow restriction is not an issue.
When sensor dry is selected, the dryer starts up and within two to three minutes, it immediately reverts from 49 minutes to 1 minute for a cool-down, and then shuts off. Now of course, in the service manual, there is that big, ominous warning that says:
"IF THERE ARE NO IMPEDANCE OR SENSOR READINGS WITHIN THE FIRST THREE MINUTES THE DRY CYCLE WILL BE TERMINATED IMMEDIATELY." (9-5)
The dryness sensor circuit of this dryer is made up of the thermistor, the sensor bars, the control board and associated wiring. Here is where the fun begins... NO
diagnostic codes are being recorded and the "System Check" activation within the Service mode of the dryness sensor circuit reports normal operations ("Normal" light is lit). To verify the diagnostics, I disconnected one wire from the thermistor and got a diagnostic code of 02 and when taped together, got diagnostic code of 01 for a short. Just to make sure and to eliminate all the parts from the equation the thermistor, sensor bars *and* the control board are all brand new (okay, the control board is refurbished, but "brand new" as to factory standard). Regardless, the problem exists just as it did before the parts were replaced.
I am completely out of ideas on this... it is driving me crazy and I refuse to be beaten by such a simple sensor circuit. Am I missing something here? Anyone have any other ideas I might try?
Barring anything else.. anyone want to buy what has rapidly become Satan in a metal box?
Thanks for your help!