Kenmore Dryer F23 Error Code — What It Means
The F23 error code on your Kenmore dryer indicates an outlet or exhaust thermistor fault. The main control board is detecting an open or invalid temperature sensor circuit at the outlet thermistor, which monitors the temperature of air leaving the drum. This is the same fault family as the F22 code on Whirlpool-built Kenmore dryers.
When this sensor circuit fails, the dryer cannot accurately measure exhaust temperature and will stop operating to prevent overheating or unsafe conditions. The fault usually points to the thermistor itself, but can also be caused by wiring problems or a failed control board.
Common Causes
- Failed outlet thermistor The thermistor has internally opened or drifted out of its normal resistance range, causing the control to see an invalid sensor reading.
- Loose or corroded thermistor connector The wire connector at the thermistor has become loose, corroded, or damaged, breaking the electrical continuity to the control board.
- Damaged wiring harness Wires between the thermistor and control board are broken, pinched, or grounded, preventing proper sensor signal transmission.
- Faulty control board sensor circuit The main electronic control board’s thermistor measurement circuit has failed, even though the thermistor and wiring test correctly.
- Corroded connector pins at P4 The control board connector terminals or harness pins have corroded or backed out, creating intermittent or open connections.
Step-by-Step Fix
- Unplug the dryer completely from the wall outlet before performing any diagnostics or repairs to prevent electric shock.
- Access the outlet thermistor by removing the front or rear panel, depending on your model. The outlet thermistor is usually mounted near the exhaust duct or blower housing where air exits the drum.
- Inspect the thermistor and its wire connector for visible damage, corrosion, loose terminals, or burned wires. Wiggle the connector gently to check for looseness and clean any corroded terminals with electrical contact cleaner.
- Disconnect the thermistor connector and measure resistance across the thermistor terminals using a multimeter set to ohms. A healthy outlet thermistor should read approximately 10,000 ohms at room temperature.
- If the thermistor reads open (infinite resistance) or significantly off from 10,000 ohms, replace the thermistor. If the reading is correct, check continuity in the wiring harness from the thermistor connector back to the main control board, paying special attention to the P4 connector and the red thermistor wires.
- Test for unintended grounds by checking continuity between each thermistor wire and the dryer cabinet ground. There should be no continuity. If the harness shows breaks or grounds, repair or replace the affected wiring.
- Reassemble the dryer, restore power, and run a test cycle. If the F23 code persists after confirming the thermistor and wiring are good, replace the main electronic control board as the sensor input circuit has likely failed.
Parts Often Needed
| Part | Notes |
|---|---|
| Outlet thermistor | Amazon | Should measure around 10,000 ohms at room temperature when working correctly. |
| Dryer wire harness | Amazon | Only needed if wires are damaged or continuity tests fail between thermistor and control. |
| Main electronic control board | Amazon | Required only if thermistor and harness both test good but the error remains. |
When to Call a Pro
Call a professional appliance technician if you are uncomfortable working with a multimeter or accessing internal dryer components. Also seek help if you have replaced the thermistor and verified all wiring but the F23 code continues to appear, as control board diagnosis and replacement requires experience with electronic components and proper part matching to your specific model. If your dryer is still under warranty, contact Kenmore service directly before attempting any repairs yourself.