Microwave Low Severity
F5 Appliance Error Code

Whirlpool Microwave F5 Error: Humidity sensor fault

If you are dealing with a whirlpool microwave f5 error, this guide will help you understand the cause and find the right solution quickly. What Does Microwave Error Code F5 Mean? Error code F5 on Whirlpool WMH, WMC, and WML series microwaves indicates a fault with the humidity or moisture sensor. Whirlpool microwaves with sensor […]

By Denys Mitchell Lead Appliance Repair Specialist

Some Steps

DIY Fixable

from $140

Typical Repair Cost

1-2 hours

Pro Repair Time

Quick Assessment

Answer to continue safely

Is it safe to keep using?

Maybe. Manual timed cooking is safe while F5 is present — the fault only disables sensor-based programs. Do not rely on Sensor Cook or Sensor Reheat functions until the fault is resolved.

Can I reset the code?

Yes. A hard reset combined with a cavity cool-down can clear F5 if the cause was temporary contamination or a hot-cavity baseline error. Sensor hardware faults will cause F5 to return on the next sensor cook attempt.

When to stop immediately?

Stop if you notice: Stop if food repeatedly burns during manual timed cooking after F5 appears — the heating system may also be malfunctioning., Stop trying DIY fixes if F5 returns immediately after cleaning and a full cool-down — sensor replacement is required..

Symptoms You May Notice

Sensor Cook function ends too early or runs too long

Before F5 is fully stored, a degrading humidity sensor may provide inaccurate readings that cause the auto-sensing cook program to terminate prematurely or overcook food.

Sensor cooking programs are greyed out or unavailable

With F5 active, the microwave disables all sensor-based cooking modes — Sensor Cook, Sensor Reheat — while manual timed cooking remains functional.

F5 appears specifically after using Sensor Cook

The error triggers only when a sensor cook program is selected, confirming the fault is in the humidity sensing circuit rather than the general control system.

Steam venting from food smells burnt but the microwave shows no heating fault

Before F5 locks out sensor modes, a contaminated sensor may fail to detect steam from overcooking food, allowing food to burn while the microwave continues heating.

Possible Causes

1

Contaminated humidity sensor

Grease and food residue coat the sensor element and alter its electrical characteristics, causing it to read humidity levels outside the calibrated range.

DIY Possible
2

Failed sensor element

The capacitive or resistive humidity sensing element degrades after years of exposure to cooking steam and eventually produces readings the board cannot interpret.

Requires Professional
3

Disconnected sensor wiring

Vibration or repeated door opening can loosen the small wiring connector to the humidity sensor, causing the board to read a no-signal condition and store F5.

DIY Possible

Safe Checks You Can Do

These checks are safe for homeowners. No disassembly required. Do not remove panels or access internal components.
  1. 1

    Allow the microwave to cool and perform a hard reset

    Unplug the microwave for 60 seconds. Leave the door open to allow the cavity to reach ambient room temperature (allow 10 minutes if the unit was recently in heavy use). Plug back in and test a Sensor Cook cycle with a cup of water.

    The humidity sensor requires a stable ambient baseline; a hot cavity from recent cooking can cause false F5 readings that resolve simply by allowing sufficient cooling time.

  2. 2

    Clean the cavity ceiling and sensor area

    With the microwave unplugged, wipe the entire cavity interior with a damp cloth, paying special attention to the top surface (ceiling) where the humidity sensor is located on WMH and WML models. Remove all grease and food residue. Allow to air dry for 10 minutes.

    Use only water or a very dilute dish soap on the cavity walls — harsh cleaners can damage the sensor element coating.

  3. 3

    Test manual timed cooking while F5 is investigated

    With power restored, confirm that manual timed cooking operates normally (set a 1-minute cook on a cup of water). Manual cooking is unaffected by F5 — you can continue using the microwave this way while arranging sensor replacement.

    If manual timed cooking also fails, the issue has progressed beyond the sensor circuit and the control board may be involved.

When to Call a Professional

Contact a qualified technician if:

  • F5 returns consistently on every Sensor Cook attempt after thorough cavity cleaning and hard reset.
  • The sensor wiring connector is secure but resistance or voltage readings at the sensor connector are outside specification.

Need Professional Help?

Find qualified technicians in your area for proper diagnostics and repair.

Microwave Repair Service Schedule Appointment

More Microwave Error Codes

View all codes →
SE PF F9 F7 F3 F2 F1