0D3

Explanation
A program check occurred; the interruption code
is X'13' for a special operation error. See Principles
of Operation for more information about special operation errors.

System action
The system abnormally ends the task experiencing
the program check.

Programmer response
Check to see if the program issued a PC
in secondary mode. Remove the Set System Mask (SSM) instruction. This
instruction is not valid in the system.

Source
Supervisor control