IBM RS/6000 - Manual (Page 214)

Table 36 (Page 2 of 5). Firmware Checkpoint Three-Digit Codes
Code Description
F22 No memory found
F23 No DIMM found in the socket
F24 Remove bad DIMM found from DIMM information
F25 Unsupported DIMM detected
F26 Check valid image - start
F27 Check valid image - successful
F28 Wait for interrupt
F29 Transfers information to the business audio chip
F2B Wait till sound chip has been initialized
F2C Initialize the current input/pointer device
F2D Initialize the current output
F2E Register a console driver
F30 Set up early memory allocation heap, Initialize Super I/O
F31 Determine system bus speed, set ISA divisor
F32 Resync to SP (Composite Image)
F33 Set memory refresh
F35 Jump to set environment
F40 Initialize interrupt subsystem and 8259s
F41 SP command setup
F42 SP Mailbox interface
F43 get_vpd entry
F44 init_sp entry
F45 sp_recovery -> resync SP & CPU
F46 IRQ13 stuck high
F47 Entry to error checking routine
F48 Power Supply or System Board problem
F49 Voltage problem. System Board, Power Supply or CPU
F4A Voltage problem. System Board or Power Supply
F4B CPU over temperature or bad System Board
F4C Start bit-map display function
F4D Bit-map file read into memory, start processing
F4E End bit-map display function
F4F IO/MEM over temperature or bad System Board
F50 Initialize CMOS RTC periodic interrupt
F51 System Board or System over temperature
F52 Bad System Board (Fan Fail reported)
F53 Bad System Board
F54 Fan fail warning
190 Introduction to PCI-Based RS/6000 Servers