I ran the washer’s self test (search for Maytag Bravos Diagnostic Modes) and found that the drain step (C7 or C8) did not drain. Definitely pointed to drain pump issue.
I followed the instructions to check the drain pump. It was clear, so used a pair of Disconnect Wire Connectors attached to the male end of an old power cord to connect the drain pump to AC power and found it would drain the washer.
My next step was to unplug the washer and then take the control head off (3 screws) to get at the control board. Before taking anything off the control board take pictures of the wiring harnesses and pressure sensor tube, then number each connector as you disconnect it. Note that the blue wires on connector P4 run to the drain pump. At this point you could order a replacement control board for about $150.
Before spending $150 I wanted to look at the control board to see if there was anything obvious. Use a wrist strap if you have one (otherwise ground yourself on one of the chassis screws) to remove the control board and place on an anti-static mat or bag. Following the blue wire connections on P4 I found that the drain pump was controlled by power relay K9 (I think that was the number - follow the traces to double check). All the solder connections looked OK so I suspected the power relay failed. I ordered a Omron G5Q-A4 DC12 from Newark Electronics ($1.37 + shipping so I got 3). With a soldering iron, solder sucker, and solder I was (after figuring out the technique) able to remove the old power relay and install a new one. Using the anti-static procedure I used earlier I re-installed the control board, reattached the connectors and pressure sensor tube, and reattached the control head.
I re-ran the washer’s self test and was very happy it completed. I have since run a few full loads and it’s still draining. Hopefully there is not a problem with any of the power circuitry on the control board or with the drain pump that will cause the relay to fail again, but only time will tell.