Of the 6 buttons on the left only the Broil button works. Most of the number pad buttons are also not working. Is there a trouble shooting procedure, or do I just need to replace the touch pad? (Membrane?)
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Parts for Whirlpool GW399LXUS04 Range - AppliancePartsPros.com
The touch pad is the most likely culprit.
Could also be the control board.
First I would unplug the unit for a couple minutes to see if it will reset.
Next I would try the below.
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. Use electronics contact cleaner or isopropyl alcohol.
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.
Next would be to check the keypad.
Unfortunately manufacturers do not publish the pin-outs for range keypads so checking it is difficult. It can be done but you need experience at this type of procedure.
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