A27

Explanation
One of the following occurred: A machine check interruption or a program check interruption occurred
The processor issued a malfunction alert (MFA) and did not enter
or remain in check-stop state
The system simulated a malfunction alert when the operator replied
alternate CPU recovery (ACR) to message IEE331A, but the processor
did not enter or remain in check-stop state

System action
The system enters wait state X'A27'.
Processing continues on other processors in the sysplex.

Operator response
To recover possible unrecorded error records,
write a stand-alone dump. Retain the dump. Contact hardware support.

Source
Loadwait/Restart