Kitchen Aid rinse issues

Hello,

We have a Kitchen Aid KUDSO1FLSS6 dishwasherwhich continually shuts off midway through any cycle. We have had a technician look at this several times without any success. The dishwasher will stop midway through a cycle and the Control Lock Sanitized Clean light flashes 7 times. The technician has showed us how to reset this although we still cannot get a full cycle out of the unit. We have checked the thermal fuse for continuity and this is working fine. Do you know if there should be something plugged into Port 12 and what might be the problem with this dishwasher. It has been used maybe 12 times in total since we purchased this from Sears and the problem was never fixed prior to our warranty running out.

Please help!

Thanks, Caroline