Maytag washer F40: water temperature sensor open or shorted
F40 (F, then 40) means the water temperature sensor used for automatic temperature control reads as an open or shorted circuit.
What F40 means
- Brand
- Maytag
- Appliance
- Top-load washer
- Code
- F40
- Documented meaning
- Water temperature sensor open or shorted
- Applies to
- 41 Maytag models on 4 platforms
- Can you keep using it?
- With caution
What the washer is detecting
Automatic temperature control blends hot and cold water using a thermistor reading. A reading that could only come from a broken or shorted circuit makes F and 40 flash.
Causes listed for this condition
In the order the service documentation checks them. Documented causes come from the manufacturer's service documentation for these platforms; possible causes are based on how the system works; unconfirmed marks common assumptions that the documentation does not support.
- Documented A failed temperature sensor or a fault in its circuit, checked with the sensor test.
Safe checks you can make
- Unplug the washer for one minute, plug it back in and start a new cycle. If the code comes straight back, the condition is persistent and needs diagnosis.
Further diagnosis requires opening the appliance. Beyond the owner checks, diagnosis involves removing panels, testing components and checking wiring. We describe what a technician investigates, not how to do it yourself.
What a technician checks
- Runs the temperature sensor test.
- Checks the sensor wiring.
Typical repairs and cost
Depending on what diagnosis finds, this code can lead to one of these repairs:
| Repair | Typical range | Labor |
|---|---|---|
| Washer water temperature sensor replacement | $180–$310 | Light |
Typical total ranges for the Las Vegas area, parts and labor included. The final cost depends on diagnosis, the exact model, parts availability and whether other damage is found.
Can you keep using it?
Use with caution. The washer may run, but water temperatures will not be controlled accurately.
Maytag models documented with this code
- MTW6300TQ
- MTW6400TQ
- MTW6500TQ
- MTW6600TB
- MTW6600TQ
- MTW6700TB
- MTW6700TQ
- MVWB350YQ
- MVWB400VQ
- MVWB455YQ
- MVWB550YQ
- MVWB700BW
- MVWB700VQ
- MVWB725BG
- MVWB725BW
- MVWB750YW
And 25 more. Use the model lookup to check yours.
Related problems and codes
Other codes documented on the same Maytag platforms:
Repair or replace?
A fault code alone rarely justifies replacing a washer. Most F40 repairs involve a single component once diagnosed. Replacement becomes worth considering when the unit is near the end of its typical 10–13-year life and the diagnosed repair is a major one. See the repair-or-replace guide.
Need F40 diagnosed in the Las Vegas area?
We repair Whirlpool, Maytag, KitchenAid, JennAir, Amana and other Whirlpool-family appliances in Las Vegas, Henderson, Summerlin and Boulder City. A model number helps but is never required to book.