My Hotpoint dish washer has stopped working - but occasional prodding of the wires (breaker off, of course) will sometimes bring it back to life. I'm seeking a solution to fix it completely.

Some history:
2 months ago it stopped working all of a sudden. We have a home warranty, so the service person came and got it going again (for $65). He said it was "a loose connection" and that he'd fixed it.

Two weeks later it stopped again. I took the bottom panel off and poked around at the wires. Put the panel back on and it ran fine for another week or two.

One week ago I'd given up, as it was broken again. My 2 year old banged on the front a bit and suddenly it was working again.

So:
Is it a loose connection underneath? In the control panel? Can I just pull and clean all the connections? Let me know what you suggest.

Thanks,
M