My dishwasher had been acting a little funky (some buttons didn’t work, some did) then it went totally dead. I replaced the main board and it came back to life, but some of the buttons work intermittently and some not at all. For instance, I have to set the timer to get the machine to run! Am I looking at replacing the pcb behind the touch pad? Help! My wife is complaining of dishpan hands!
Here is your parts breakdown.
http://www.appliancepartspros.com/partsearch/modelsearch.aspx?model=pld2850rdc2
Here is the tech sheet for this unit
http://manuals.frigidaire.com/prodinfo_pdf/Kinston/154493101en.pdf
See Section 1.
Item 3 is the control board, I am assuming this is what you replaced.
Item 8 looks like just a display board so I doubt it is your problem.
Item 2 insert is the keypad, this is the likely culprit.
You could try the following.
Connector Cleaning / Checking
Unplug the unit
Open it up
Remove the ribbon cable from the keypad to the control board at the control board.
Clean the edge connector.
If it is the type where there is not a connector just the insulation is removed, it can be cleaned with a pencil eraser. Do not use an ink eraser as it is too abrasive.
Check the tracks in the ribbon cable for hairline cracks. A magnifying glass helps here.
Would not hurt to clean the connector on the board. Use electronics contact cleaner or isopropyl alcohol and a tooth brush. Be gentle and do not reconnect till all the solvent evaporates.
Reconnect everything and give it a try.