053

Explanation
There is not enough system queue area (SQA) storage available to initialize all of the I/O
devices that are defined in the I/O configuration. The right-most four bytes of the program status
word (PSW) have the following format:
rrrxxwww
where: 

rrr

A hexadecimal reason code indicating the reason for the failure

xx

Reserved

www

The wait state code

The reason code (rrr) is one of the following values: 

000

The system could not obtain enough system queue area (SQA) storage.

001

The system could not obtain enough extended system queue area (ESQA) storage.

System action
The system enters wait state X'053'.

Operator response
Notify the system programmer.

System programmer response
Contact IBM® Support to report this error. Modify the
virtual storage allocated to the system queue area using the INITSQA keyword in the
LOADxx member of parmlib.

Source
I/O Supervisor (IOS)