I just added a Parity 2 Drive to my array this week.

I ran it through preclear first and then added to the array.

It added to the array just fine and was working for the last few days until this AM.

 

 

I started a parity check, but I am not sure that will fix the issue.

This is what I see when trying to check SMART status.

 

 

Is the drive just bad? Is there something else I need to check or run?

 

Parity 2 has dropped off line. Tools -> Diagnostics before rebooting. Attach the zip to your next post.

I did some googling and saw a lot of similar issues were connection related.

I switched out the sata cable and all is good for now. 

Since you didn't give us a diagnostic I can't tell. Was that first screenshot the entire array? Dual parity for a single data disk?