Stand Mixer: Why does my stand mixer run on high speed only?

The phase control board helps control motor speed on mixers that use a speed control plate to control the motor. A failed phase control board or a wiring failure can cause the mixer to run on high speed only. On mixers that use an electronic control board to control motor speed, a bad electronic control board can cause the mixer to run on high speed only.

If your mixer has a removable cover on the back end of the motor housing, then the mixer uses a speed control plate and phase control board to control motor speed. Unplug the mixer and remove the back motor housing cover. Check the wire connections between the speed control plate and the phase control board. Reconnect any loose wires and repair any broken wires. If the phase control board wire connections are okay, you'll likely need to replace the phase control board because it isn't helping control motor speed.

If your mixer doesn't have a removable back cover on the motor housing then the mixer likely uses an electronic control board to control motor speed. If your mixer uses an electronic control board to control the motor, unplug the mixer and replace the electronic control board if the motor runs only on high speed.

stand mixer

THESE REPAIRS MAY HELP SOLVE YOUR STAND MIXER PROBLEM

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Replace the stand mixer phase control board

The phase control board works with the governor and control plate to monitor and control motor speed. If the mixer won't run or it doesn't maintain the set speed properly, then you may need to replace the phase control board.

Stand mixer phase control board

Find the required part specific to your product.

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September 20, 2015By Lyle Weischwill

How to replace a stand mixer phase control board

If your stand mixer isn't mixing at the speed you set, the phase control board could be the problem. This step-by-step repair guide and video show how to replace a stand mixer phase control board in about 30 minutes.

Repair difficulty
Time required
 30 minutes or less

Symptoms common to all stand mixers

Choose a symptom to see related stand mixer repairs.

Main cause: attachment clearance setting needs adjustment
Main causes: lack of electrical power, wiring failure, worn carbon motor brushes, bad drive motor, tripped overload switch, control problems
Main causes: bad lubricating grease, mixer sitting idle for weeks at a time, mixer running constantly for more than 30 minutes
Main cause: worn carbon motor brushes
Main causes: phase control board failure, wiring connection problem, faulty electronic control board
Main causes: bad wiring connections, faulty speed control plate, electronic control board failure
Main causes: bad worm gear, damaged planetary gear assembly

Repair guides common to all stand mixers

These step-by-step repair guides will help you safely fix what’s broken on your stand mixer.

September 20, 2015
By Lyle Weischwill
How to replace a stand mixer worm gear

Here’s how to replace the worm gear in your stand mixer if it’s worn or damaged.

Repair difficulty
Time required
 30 minutes or less
September 20, 2015
By Lyle Weischwill
How to replace a stand mixer phase control board

The phase control board works with the governor and control plate to control motor speed. Replace the phase control board if defective.

Repair difficulty
Time required
 30 minutes or less
September 1, 2015
By Lyle Weischwill
How to replace stand mixer motor brushes

If the carbon brushes are worn and damaged, replace them using these steps.

Repair difficulty
Time required
 15 minutes or less

Articles and videos common to all stand mixers

Use the advice and tips in these articles and videos to get the most out of your stand mixer.

August 18, 2021

Using a wiring schematic to trace a current video

By Sears PartsDirect staff

Find out what’s wrong with your appliance by following a circuit.

December 2, 2015

How to make Irish shortbread toffee bars

By Sears PartsDirect staff

These toffee bars combine caramel and chocolate in layers for an ooey-gooey treat.

September 1, 2015

Stand mixer common questions

By Sears PartsDirect staff

These common questions and answers can help you make the most of your stand mixer.