Why does washing machine stop before draining from wash cycle?

I recently installed a new drain pump assembly on my Fisher & Paykel washing machine (model no. GWL15US, product no. 96155-B). That installation, which included inatalling a fuse in the power supply, was successful; and the machine ran perfectly thereafter. However, it now stops before the rinse cycle, leaving contents and wash water from washing cycle in tub. The machine beeps a monotone (inaudible to my deaf ears), but there are no flashing lights. If I stop, power down, and restart the machine, it repeats the same behavior, but starting with the wash cycle agitation, as the tub is already full of water and wash load. I suspect that something might be wrong with that new pump and/or its connections, although all of those latter seem secure; and the fuse has not blown. One last possibly relevant detail: this problem arose after the the machine had repeatedly stopped and restarted itself due to an unbalanced spin load. So, any notion what's going on here? More particularly, should I--and how might I--test the status of the pump motor? With thanks, Roby