From the AIX Version 4.3 Messages Guide and Reference :
Display Value 554
Explanation
The IPL device could not be opened or a read failed (hardware not configured or missing).
System Action
The system halts.
User Action
Go to "Hardware Diagnostics" in in AIX Problem Solving Guide and Reference to determine if there is a problem with the device where the files reside.
If these procedures do not find a problem with a device, the problem is usually due to bad information on the boot logical volume, or the log logical volume (/dev/hd8) has been damaged.
To correct the problem with the boot logical volume, enter Maintenance mode (refer to "Accessing a System That Will Not Boot" for information on loading the Maintenance mode onto your system), then run the savebase command. When the savebase command completes, issue the sync; sync command. After this command completes, restart the system in Normal mode.
If this does not correct the problem, reenter Maintenance mode and enter the /usr/sbin/logform /dev/hd8 command. When this command completes, restart the system in Normal mode.
If you are not familiar with this mode or are unable to correct the problem, report the problem to your software service organization, and then stop. You have completed these procedures.
... for what it's worth. Maybe a bit late though
B.