Howto enable DIAG when marked as disabled in V$DIAG_INFO?

Howto enable DIAG when marked as disabled in V$DIAG_INFO?

  1* select * from V$DIAG_INFO

SQL> /

   INST_ID NAME                 VALUE                                        CON_ID

---------- -------------------- ---------------------------------------- ----------

         1 Diag Enabled         FALSE                                             0

         1 ADR Base                                                               0

         1 ADR Home                                                               0

         1 Diag Trace           C:\ORACLE\PRODUCT\12.1.0.2\RDBMS\TRACE            0

         1 Diag Alert           C:\ORACLE\PRODUCT\12.1.0.2\RDBMS\TRACE            0

         1 Diag Incident                                                          0

         1 Diag Cdump           E:\BUKAI\diag\rdbms\bukai\bukai\trace             0

         1 Health Monitor                                                         0

         1 Default Trace File                                                     0

         1 Active Problem Count                                                   0

         1 Active Incident Coun                                                   0

   INST_ID NAME                 VALUE                                        CON_ID

---------- -------------------- ---------------------------------------- ----------

           t

11 rows selected.

SQL> show parameter diag

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

diagnostic_dest                      string      E:\BUKAI