CA-7.X002 (10 01AE) DISPLAY FAILED, R15 = 0000000C received when trying to logon to CA 7 via ISPF.
The error message "CA-7.X002 (10 01AE) DISPLAY FAILED, R15 = 0000000C" suggests that a missing panel "CA7P000" in the ISPPLIB.
Copy the panels CA7@PRIM, CA7P000, CA700003 into the ISPPLIB DD dataset that is allocated to your TSO session.