I have an SHU5316UC bosch dishwasher that has a lot of the same symptoms you described here: the very long cycles, counting down to 1 and never shutting off, then finally the dreaded 2H code. After reading all the posts here, I replaced the control module and found the repair to be fairly easy.
However, it still is not working.
the 2H code is gone, but the machine isn't pumping water into the dishwasher.
I pulled out the microfilter and the screen down in the sump, dried out the water, checked for obvious blockage, cleaned and replaced all the parts.
And the timer seems to be wacky -- a regular cycle only gets 42 minutes -- when I thought that the regular cycle was more like 72 or 90 minutes long.
Does anybody have suggestions on what to try next?