Our six year old Kenmore HE2Plus washer is flashing code F-28 about every third wash during its final spin. It's really irritating my wife as she has to stop the cycle and rerun the Rinse/Drain & Spin again, which washes out the fabric softener.
I researched this on the web and did not find a straight-forward solution. Some folks have replaced the motor controller unit (MCU), others the central control unit (CCU), others both, and results are sketchy . Another thing mentioned frequently is checking all electrical contacts between these units.
If you have fixed this problem on an HE2Plus I'd appreciate hearing what you did.