My Frigidaire freezer stopped freezing. I checked the Compressor and start relay, both OK. Coil fan is working fine. User interface is not working. Does not turn on. I think this explains the fact that the freezer cools but does not freeze hard.

Here's my question. Since there are two control boards - main and user and the user board is slaved to the main board, which board is bad? Would a failure in the main board cause the user board to not work at all? Is there a way to check the boards before I replace them?

Thanks.