Whirlpool Dishwasher

[Tarheel Technician]

Checked a dishwasher, model #: DU920PFGQ2 that will not do anything.

I verified voltage to the machine, ruled out the door switch, and the TCO.

I'm getting voltage at the control board across P8 and P7.

I think I either have a bad control board or a bad touchpad. I have a nifty little dishwasher touchpad checker that I can hook the ribbon connector up to, but the tech sheet I have does not give any information regarding which connections should open when pressing a certain keypad. (no user interface matrix).

I tried pushing the normal keypad, then checking every possible combination of the ribbon connectors for resistance. I got infinite resistance with every combination, so I'm thinking I have a bad touchpad.

I just wanted to see if there was anything else I could do to verify that it's actually the touchpad and not the control board. Thanks in advance for any info.

[buschman]

i think there's a fuse on that board, it's a plug in. look for a removable fuse near the top of the board, pull it out and check it for continuity....

[Samurai Appliance Repair Man]

[user=161]Tarheel Technician[/user] wrote:

I tried pushing the normal keypad, then checking every possible combination of the ribbon connectors for resistance. I got infinite resistance with every combination, so I'm thinking I have a bad touchpad.

Absent any diagram of the touchpad matrix, this is as good as you can do. Try checking a few other buttons. If you can't find a button that does yield a matrix combo with continuity, then the possibilities are 1) you're somehow measuring wrong or 2) that touchpad is FUBAR.

[Tarheel Technician]

Well, after going back and re-checking the touchpad, I still could not get any continuity. I tried every combination, on 4 or 5 different buttons. I could get the lights to come on when I touched the right combinations (I had the power cut off, but it was getting the DC voltage from my meter). But as far as continuity closing and opening when any button was pushed, nada.

Guess I'll be ordering a touchpad for this unit.

[Samurai Appliance Repair Man]

I would do the same thing in these circumstances.