How to troubleshoot an F28 error code in a Whirlpool Duet Sport washer
OK ... going by memory here.
- First ohm out your motor. You should have approx 6 ohms between 1-2,1-3 and 2-3. You should also get 120 ohms on 5-6 which is the tach on the motor. If that is good ...
- Open up the little flap on the MCU board. Start a regular wash cycle and check for voltages at the MCU. On the pink wires you should get 120v. (With the wires connected to the MCU - don't disconnect them to check the voltage.) On the connector with the little blue wires - you should have 5 vDC.
- If you are getting the correct voltages at the MCU and the motor ohms out good, then you have a bad MCU.
- If you are not getting those readings at the MCU, then check continuity on the blue wires and the 2 pink wires from the CCU to the MCU.
- If you have continuity on all wires and the connections look good, then you have a bad CCU.
Part links ==> MCU, CCU
Source: whirlpool duet wfw9200sq00