Customer Questions and Answers for Dryer Moisture Sensor Bar by Whirlpool

Jerry, This error code is an indication of the moisture sensor being open. TEST #4 Moisture Sensor NOTE: This test is started with the dryer completely assembled. This test is performed when an automatic cycle stops too soon, or runsmuch longer than expected. NOTE: Dryer will shut down automatically after 2-1/2 hours. The following items are part of this system: Harness/connection Metal sensor strips Machine control electronics. See ESD information, page 1. 1. Enter Service Diagnostic mode and select the User Interface/Control System test. See procedure on page 5. 2. Open the dryer door. The dryer should beep and an alphanumeric number should be displayed (on models with seven segment display) or the TEMP, TEMP LEVEL, or DRY TEMP indicators should change (on models without seven segment display). 3. Locate the two metal sensor strips on the face of the lint screen housing. Bridge these strips with a wet cloth or finger.  If a beep tone is heard and an alphanumeric number is displayed on the console (on models with seven segment display) or the TEMP,TEMP LEVEL, or DRY TEMP and STATUS indicators change (on models without seven segment display), the sensor passed the test. Go to step 9.  If a beep tone is not heard, or a continuous beep tone is heard before bridging the moisture strips, continue with step 4. NOTE: Overdrying may be caused by a short circuit in the sensor system. 4. Unplug dryer or disconnect power. 5. Access the moisture sensor wires by removing the toe panel. Disconnect the sensor wires from the harness. See figure 11. 6.Access the machine control electronics. See Accessing & Removing the Electronic Assemblies, page 23. Remove connector P13 from the circuit board. Check the main harness connections between the sensor harness and machine control for a short or open circuit.  Replace the main harness, if necessary.  If harness is OK, continue with step 7. 7. Measure the resistance across the outermost contacts of the cable that includes the two red MOVs.  If a small resistance is measured, check for debris across moisture strips inside the drum; clean if debris is present. If debris is not present, replace sensor harness.  If a small resistance is not measured, continue with step 8. 8. Measure the resistance across each of the outermost contacts and the center terminal (ground connection).  If a resistance less than infinity is measured, replace the sensor harness. 9. Ifmoisture sensor diagnostic test passes, check the thermistor: PerformTEST #3a, page 19.  If the problem persists after replacing the moisture sensor and thermistor, replace the machine control electronics.