Hi my name isXXXXX have been an appliance
repair tech since 1992.
With the symptons you described, the mother board has failed. This board is located on the back lower portion of the refrigerator. You will have to gently pull the refrigerator out and find the small access plate and remove part# XXXXX
Here is a diagram: https://genet.geappliances.com/IPCNet/Dispatcher?REQUEST=GEAIPCNETGETPDF&file=00000000/00047800/00047883.p02.pdf&modelNumber=PSC23NSTASS
Easy to remove and replace , wire to wire harness connections.
Here is a good video on the replacement board instructions:
The part is #801 on diagram.
You can use Repairclinic.com to purchase it or use Google search fro best price shopping.
Hope this helps you.
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