Hi all – This great forum helped me repair my wall oven recently, and now I’m working on my dishwasher (about 10 years old). It has been blowing thermal fuses for over a year - 18mos… i’m on my 5th thermal fuse. Sometimes they last several months, sometimes only weeks. Every time a fuse blows, there is water in the bottom. With a fresh fuse, press Cancel and it pumps out. But this time, replace the fuse, and it wont drain. No noise, no humming, nothing. Indicator lights are on, but wont drain. I figured the drain pump was failing, drawing too much current, blowing fuses, and now its failed and the motor wont run. So to test this theory I checked resistance at the pump (unplugged) and get about 10 ohms - what should this value be? The impeller spins as it should and is not damaged. Drain line appears unobstructed. I then checked voltage at the drain pump terminals (by pressing Cancel) and get zero volts. I’ve read that pressing Cancel should send 120v to the pump, and would indicate a bad control board. BUT - Does there need to be water in the basin to trigger voltage at the pump? There is no water in there (drained it out manually when I removed the unit, and I dont want to pour a gallon in there to test it, only to have to drain it again to work on it).
So a few questions - what resistance should the drain pump motor read? Does there need to be water in the basin to get 120v at the drain pump terminals? or is pressing Cancel enough? Any other thoughts or suggestions?
Many thanks!!