Whirlpool Washer - F40 Error Code

Water level or pressure system error.

Meaning

Water level or pressure system error.

The F40 error indicates that the washer’s pressure system is not providing valid water level information. Whirlpool Duet washers use a pressure switch or analog pressure sensor to monitor water level. If the sensor output is missing, out of range, or inconsistent with the washer’s fill stage, the washer triggers F40. This error is less common but typically indicates a failing pressure sensor or wiring issue.

Symptoms

  • Washer stops during sensing
  • Washer fills and drains repeatedly
  • F40 appears early in the cycle
  • Incorrect water levels

Causes

  • Failed pressure sensor
  • Blocked pressure hose
  • Loose or damaged wiring harness
  • Control board misreading sensor output
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Step-by-Step Fixes

  • Inspect the pressure hose for blockages.
  • Ensure the hose is firmly connected.
  • Test the pressure sensor with a multimeter.
  • Replace the sensor if readings are out of range.
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Safety Notes

  • Disconnect power before servicing the pressure system.
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Applicable Models

Show Models
  • WFW9200SQ
  • WFW9400SW
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Related Pages

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Other Whirlpool Washer Error Codes

Show All Error Codes

Model-Specific Notes

On Duet models, F40 often appears when the pressure hose becomes partially blocked by detergent residue or lint.

Disclaimer

The information provided on this page is for educational and informational purposes only. Repairs involve electrical, mechanical, and water-related risks. Always follow manufacturer instructions and consider contacting a qualified technician for diagnosis or repair.

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