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Error code reference

Maytag Oven Error Code 4d21

No reverse airflow fan rotation detected (no or low RPM) during cook or clean (upper oven or single cavity).

Maytag codesMaytag oven codes
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What the 4d21 error code actually means

Your oven has detected that the convection fan inside the upper oven cavity has stopped spinning or is not spinning fast enough during cooking or cleaning. To protect your oven from overheating, the appliance has automatically shut down the cooking functions until this problem is resolved. This is typically a sign that the convection fan motor needs to be inspected or replaced by a technician.

Diagnostic procedure

The full 4d21 procedure

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1
First diagnostic step
Check convection fan motor and wiring; disables all cooking functions for cavity.
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Most common causes of 4d21

Ranked by how often they cause this code
  1. 1Failed convection fan motor
  2. 2Broken or disconnected wiring harness to fan motor
  3. 3Fan blade obstruction or damage
  4. 4Faulty oven control board

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Questions people ask about 4d21

What does error code 4d21 mean on a Maytag oven?
Code 4d21 means the oven's control board detected no rotation or insufficient RPM from the reverse airflow convection fan motor in the upper or single oven cavity during a cook or clean cycle. The oven disables all cooking functions for the cavity when this fault is active. You need to inspect the convection fan motor, fan blade, and wiring harness to identify the source of the problem.
How do I fix error code 4d21 on a Maytag oven?
Start by disconnecting power to the oven and accessing the convection fan motor at the back of the upper cavity. Check the fan blade for obstructions or damage and spin it by hand to feel for resistance. Inspect the wiring harness to the motor for loose connectors, burned wires, or breaks. If the wiring and blade are intact, test the motor for continuity with a multimeter; a reading outside spec confirms the motor needs replacement. If the motor and wiring test fine, the control board may need replacement.
Will clearing the 4d21 code fix my Maytag oven, or will it come back?
Resetting the code by cycling power will temporarily clear it, but 4d21 will return as soon as the oven attempts to run the convection fan and detects the same problem. The fault will persist until the underlying cause, whether a failed motor, damaged wiring, or obstructed fan blade, is physically repaired. Do not rely on resets as a fix.
Can I still use my Maytag oven with a 4d21 error code?
No. Code 4d21 disables all cooking functions for the affected cavity, so baking, broiling, and self-clean will not operate until the fault is cleared. Attempting to force a cycle while the fan is not rotating could cause uneven temperatures or overheating inside the cavity. Repair the fan motor or wiring issue before using the oven again.
How much does it cost to fix a 4d21 error code on a Maytag oven?
A replacement convection fan motor for a Maytag oven typically costs between $40 and $120 for the part, depending on the model. If you hire a technician, expect $150 to $300 total including labor for a motor replacement. Replacing only the wiring harness or clearing an obstruction costs significantly less. A control board replacement is the most expensive repair, often $200 to $400 or more with labor, which is why the board should be ruled out last.

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