No, power down, disconnect old parity and new disk2, connect new parity and old disk2, array won't start because some disks will be missing, ignore, follow steps above.
-Tools -> New Config -> Retain current configuration: All -> Apply
-Assign old disk2 as disk2
-Assign new parity
-Start array to begin parity sync
Note: Any data written to disk2 after the upgrade will be lost
Rebuilt disk will likely have some corrupt data, unless by chance the read errors on parity coincided with empty sectors on disk2, if you still have the old disk use it to re-sync with a new parity then upgrade again.
Problem was because IRQ16 got disabled, we'd need to see what's using it but it's usually harmless unless you have a SASLP/SAS2LP, and you don't, also very unlikely to be preclear related, though like trurl mentioned not everything should/needs to be precleared.
To rebuild disk 16:
-stop the array
-re-assign disk16 - icon should turn blue
-start the array to begin rebuilding
Any doubts please ask.
When it's done rebuilding post a new screenshot