F40
What code F40 means on a Kenmore washing machines, what causes it, and which part to check first.
● SEVERITY: HIGH
Kenmore F40 means: Water temperature thermistor failure. The documented cause is: UThe inlet water temperature thermistor (temperature sensor) is integrated into the inlet water valve assembly.
What F40 means
Water temperature thermistor failure
The display shows F40 and the machine stops until the fault is cleared.
What the technical documentation says
Causes documented in the technical source published by applianceaid.com
| DOCUMENTED CAUSE OR CHECK |
|---|
| UThe inlet water temperature thermistor (temperature sensor) is integrated into the inlet water valve assembly |
| Unplug the washer and check the wire harness connection between the main electronic control board and the thermistor on the inlet water valve assembly inside the console |
| If the wiring harness connection is okay, then the inlet water valve assembly will usually need to be replaced |
Replacement parts
Tools you'll need
Before you open anything
Unplug the machine and close the water tap before removing any panel. Water and mains electricity sit centimetres apart inside a washing machine. If the drum still holds water, drain it from the filter first — it can be scalding.
What to check, in order
From the quickest check to the one that needs a technician.

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Frequently asked questions
What does F40 mean on a Kenmore?
Water temperature thermistor failure The documented cause is: UThe inlet water temperature thermistor (temperature sensor) is integrated into the inlet water valve assembly. Unplug the washer and check the wire harness connection between the main electronic control board and the thermistor on the inlet water valve assembly inside the console. If the wiring harness connection is okay, then the inlet water valve assembly will usually need to be replaced
Can I fix F40 myself?
It depends on the part involved: UThe inlet water temperature thermistor (temperature sensor) is integrated into the inlet water valve assembly. Unplug the washer and check the wire harness connection between the main electronic control board and the thermistor on the inlet water valve assembly inside the console. If the wiring harness connection is okay, then the inlet water valve assembly will usually need to be replaced Clearing a filter or straightening a hose is within reach of anyone; anything behind a panel means mains electricity and water together — that is a job for a technician.
Does Kenmore use other codes on this appliance?
Yes: we document 142 other codes for Kenmore on this washing machines. They are listed at the bottom of this page, each with its own meaning.
Does the same code mean the same thing on other brands?
Often not. The same two characters can point to completely different faults depending on the manufacturer — always check the page for your own brand.

