Microwave Loud or Noisy

If your microwave is making unusual or loud noises, the problem could be caused by a worn turntable motor, failing magnetron, damaged cooling fan, or another internal component. Before replacing any parts, inspect the most common causes listed below.

Safety Notice: Always unplug the microwave before servicing it. Microwaves contain high-voltage components that can retain a dangerous electrical charge even after being disconnected from power.

Possible Causes

  1. Worn turntable motor
  2. Failed magnetron
  3. Damaged cooling fan motor
  4. Faulty high-voltage diode
  5. Damaged turntable roller guide
  6. Loose internal components
  7. Defective stirrer motor (select models)
  8. Worn drive coupler

1. Turntable Motor

Most Common Solution

The turntable motor rotates the glass tray during cooking. If the motor becomes worn or damaged, it can produce grinding, humming, or clicking noises.

What to do:

  • Disconnect power to the microwave.
  • Remove the glass tray and roller guide.
  • Listen for noise coming from beneath the turntable.
  • Replace the turntable motor if it is noisy or does not rotate smoothly.

2. Magnetron

The magnetron generates the microwaves that heat food. As it begins to fail, it may produce a loud humming, buzzing, or growling noise during operation.

What to do:

  • Listen for noise while the microwave is heating.
  • Inspect the magnetron for signs of overheating or damage.
  • Replace the magnetron if it is defective. Professional installation is recommended.

3. Cooling Fan Motor

The cooling fan prevents internal components from overheating. Worn bearings or damaged fan blades can create rattling, squealing, or buzzing noises.

What to do:

  • Inspect the cooling fan for debris or damage.
  • Verify the fan blades spin freely.
  • Replace the fan motor if it is noisy or defective.

4. High-Voltage Diode

A failing high-voltage diode may produce a loud buzzing or humming sound while preventing the microwave from heating properly.

What to do:

  • Disconnect power to the microwave.
  • Test the diode using the appropriate test equipment.
  • Replace the diode if it is defective.

5. Turntable Roller Guide

The roller guide supports the glass tray as it rotates. Dirt, wear, or broken rollers can cause scraping or rattling noises.

What to do:

  • Remove the glass tray and roller guide.
  • Clean away food debris.
  • Inspect the rollers for wear or damage.
  • Replace the roller guide if necessary.

6. Loose Internal Components

Loose screws, brackets, or internal panels can vibrate during operation and create rattling noises.

What to do:

  • Disconnect power to the microwave.
  • Inspect accessible hardware for looseness.
  • Tighten any loose screws or mounting brackets.

7. Stirrer Motor (Select Models)

Some microwave models use a stirrer motor to distribute microwave energy evenly. A failing stirrer motor may create clicking, grinding, or buzzing noises.

What to do:

  • Determine if your microwave is equipped with a stirrer motor.
  • Listen for noise coming from the top of the microwave cavity.
  • Replace the stirrer motor if it is defective.

8. Drive Coupler

The drive coupler connects the turntable motor to the glass tray. A cracked or worn coupler can produce clicking or grinding noises while the turntable rotates.

What to do:

  • Remove the glass tray.
  • Inspect the drive coupler for cracks or excessive wear.
  • Replace the coupler if it is damaged.

Need Help Finding the Correct Part?

If you need help identifying the correct replacement part, send us your complete microwave model number and a clear photo of the appliance identification label before placing your order. Our team will verify compatibility and help ensure you receive the correct replacement part the first time.