I am happy to say I have run 20 loads of various types without any error codes.
The repeat maintenance I performed was the CLR decalcification clean under the system clean cycle of hot water cycle (such as towels).
When the error E03 occurred I:
Vacuumed the drain port while the pump was draining. Repeated until door lock opened.
Placed CLR in all the dispenser trays (total) 1/8 cup.
Added 1/4 cup of baking soda to the bin
Ran a hot cycle or the system clean cycle
On the next load I added only 1/2 the normal amount of clothes for 4 load cycles.
Used 2 Table Spoons of Tide HE laundry detergent
and 2 Tables Spoons of Softener.
Ran hot water cycles
Repeated the cleaning cycle with CLR after each cycle.
Now the E03 error is gone and the washer runs consistently.
I believe this cleaning method is a first diagnostic approach to help isolate any other issues. It can save on any physical repair or call to a tech.