04B

Explanation
An incorrect operation code was passed to a TSO
linkage assist routine (LAR). Register 15 contains a hexadecimal code
that indicates the reason for the termination. Code
Explanation
004
The LAR for the terminal monitor program received an incorrect
function number.
008
The service routine's LAR was invoked an incorrect service routine
entry point.

System action
TSO does not perform the requested service. The
system writes an ABEND dump. The system writes a logrec data set error
record.

System programmer response
If the problem recurs and if the program
is not in error, search problem reporting data bases for a fix for
the problem. If no fix exists, contact the IBM® Support Center. Provide the ABEND dump and
the logrec data set record.

Programmer response
Determine the calling routine and correct
the operation code.

Source
Time Sharing Option Extensions (TSO/E)