Kenmore Elite HE3t Washing Machine F20 Error code

Good day:

I own a 2008 Kenmore Elite HE3t Washing Machine, I had the infamous F35 code and I replaced the pressure switch a year ago. Now I have error code F20, I have so far check the pressure switch rubber hose for obstructions, the water meter switch is running fine, as I get a water level up to the bottom of the front door, don't suspect a leak, as I let the water sit for 10 minute, without level drop. The code comes up at the 44 minute remain mark. Is there something I'm missing or do I need to replace something else?