KitchenAid Microwave Error Code 4d22: Meaning and Fix
Reading the microwave display
On a microwave the code replaces the clock on the display. Unplug the unit for a minute to see if it clears, and note the code before you do. KitchenAid pairs the number with a letter group in the manual, so match the exact characters.
KitchenAid is Whirlpool Corporation's premium appliance line. Its dishwashers, ranges, microwaves and refrigerators share Whirlpool boards but use their own panel layouts and numbering in the manuals. The codes apply to model numbers such as KUDS24SEWH1, KUDS01DJSS0 and KHMS155LSS4; check the label on your unit to confirm yours.
What causes 4d22
- Defrost heater, sensor or timer has failed and frost is blocking airflow
- Door gasket is leaking warm air
- Evaporator or condenser fan is not running
- Damper or air duct is stuck or iced over
- Compressor start components or the sealed system are failing
How to fix it
- Cycle the power: unplug the microwave (or switch off its breaker) for one minute, restore power and test it briefly with a cup of water.
- Before opening any panel, switch off the breaker or unplug the appliance; this circuit can carry line voltage.
- Check that the doors seal and nothing keeps them from closing; look for frost build-up on the back wall of the freezer.
- Listen for the evaporator and condenser fans and confirm both turn freely.
- Unplug the unit with the doors open for several hours to melt any frost fully, then restart and watch temperatures over 24 hours.
- If frost returns, test the defrost heater, sensor and fans in turn and replace the one that fails; call a technician for sealed-system faults.
- Run a full short cycle or function again and confirm the code stays gone before putting the appliance back into normal use.
Parts you may need
| Part | Part no. | Buy |
|---|---|---|
| Inverter | W10217710 | Find part |
Part numbers are OEM references; confirm fit by your model number before ordering. Some links are affiliate links; we may earn a commission at no extra cost to you.
Questions
What does 4d22 mean on a KitchenAid microwave?
It is a fault code from the KitchenAid control. It indicates a problem with the cooling system. A power reset is the first thing to try.
Can I keep using the microwave while it shows 4d22?
Stop using it until it has been checked. This fault involves heat, high voltage or sealed-system parts, and running it can damage the appliance or create a safety risk.
Do I need a technician to clear 4d22?
Often yes. Part of this repair means testing live circuits or replacing a control board, so a technician is the safer choice unless you are comfortable with electrical diagnosis.
Other KitchenAid microwave codes
Sources
Part numbers are OEM references; confirm fit by your model number before ordering. Meanings compiled from manufacturer and parts-retailer documentation; see sources below. Unplug the appliance before opening it.
Applies to models including KHMS155LSS4, KHMS155LSS1, KHMS155LSS0, KHMS1850SSS0, KHMS145JWH0, KHMS145KSS0, KHMS155LSS3, KHMS2050SSS0.