Whirlpool Duet Front-loader ... was giving F21 (slow drain). Fixed this 2-3 weeks ago by cleaning out pump filter and drain hose. Now, several dozen loads later, seems like it is not spinning excess water from clothes. Gives the F21 again. Ran diagnostic test, and display goes out after step C06. During step C06 pump seems OK and pumping out water from drum. Once that step completes C07 (and subsequently C08) is not displayed, and the drum does not reverse direction and spin at high speed, however I can hear the motor running.