52D

Explanation
A program requested an overlay.  The overlay supervisor
called the program loader to obtain the module segment from a linear
format data set (such as a PDSE), and the program loader encountered
a problem while processing the request. 

System action
The system abnormally ends the program that requested
the overlay. The system writes an ABEND dump, if a dump DD statement
is provided. In addition, the program loader may issue ABEND0F4 and
an SVCDUMP.

Programmer response
If an ABEND0F4 was issued, see the information
in this manual for that abend.  Otherwise, check the program
for errors that might cause a problem with the overlay segment table.
 Correct any errors; then assemble, link edit, and run the program
again.

Source
Overlay supervisor