Brand:Whirlpool Model Number:MBF1958DEE00 Main Symptom:Warm fridge about half the time, with large temperature swings between cycles. What happens & when:Temperature swings of about 10 degrees keep fridge between 35-45 degrees. Cycle on time is about 40 minutes then cycles off for 20 minutes. Freezer is at 0 degrees, coils are clean, door seals are good, fridge is not overloaded. This fridge is about 10 years old. Changing temperature setting from 3 to 4 (colder) changes temp by a couple of degrees, but otherwise same symptoms. Wonder if control board is most likely issue, or perhaps more troubleshooting could be done?
Error Code (if any):
Parts or tests already tried:
Photos / video link:
Additional data collection, after increasing cooling from 4 to 5 shows same peaks of 40 degrees before the on cycle, but continues cooling to 28 (rather than 35). Hope this makes sense.
For Maytag MBF1958DEE00, WPW10594330 is the correct refrigerator electronic air damper.
To test it through diagnostics:
Hold the refrigerator door/light switch closed.
Press Refrigerator Temperature UP (+) 3 times within 10 seconds.
Release the door switch.
Display should show S–E.
Press Refrigerator UP (+) once to enter diagnostics.
Use the Freezer UP/DOWN buttons to go to Service Test 6.
Test 6 = Damper Test.
Press Refrigerator UP (+) to toggle:
O = Open
C = Closed
Allow up to 1 minute for the damper to change position.
What you’re looking for
If you command O and the WPW10594330 doesn’t physically open, then command C and it doesn’t move, suspect either the damper assembly or its power/control circuit.
For this model, I’d also run Test 4 — Fresh Food Thermistor. It should report P = Pass. An open/shorted fresh-food thermistor can affect the control’s decision to operate the dam
I did a visual inspection of damper, and it’s opening and closing. Getting 10 deg. temp measured at the opening.
Note, there was a tiny piece of styrofoam at the left corner of the damper housing. Maybe this small, bb-size chunk was preventing it from closing completely.
Will continue to monitor temp swings and update here.
Another 24 hours shows temp cycles swing continue, between 27 and 42.
Are there other checks to be done? It seems like diagnostics cleared the thermistor, and I viewed the damper opening and closing, with 10 degree air coming up from freezer.
Would the only remaining suspect be the control board?
Hi, just double checking parts. The instruction video shows disconnecting the thermistor from the housing where the control board is mounted. But I don’t see it on the control board.
Is the thermistor integrated into board? On the close-up, I don’t see anything that looks like it senses air temperature.
Would like to try thermistor first if possible.
Whirlpool parts says this fits my fridge MBF1958DEE00. Does that seem wrong?
Final note: I was able to see that the thermistor is integrated into the harness. However, since it already passed the diagnostic test, the only other suspect is as you say the control board, which I’ll replace.
Thank you for your time helping troubleshoot! All set now.
