Appendix A. Interpreting Firmware Error CodesThe error code is an 8-character (4-byte) hexadecimal code produced by firmware toidentify the potential failing function or FRU in a system. It consists of 5 source codecharacters and 3 reason code characters. Individual characters within the error codehave specific field definitions, as defined in the following tables. Table A-1 andTable A-2.Table A-1. Service Reference Code Field LayoutSource Code Reason CodeByte 0 Byte 1 Byte 2 Byte 3S1 S2 S3 S4 S5 R1 R2 R3Table A-2 (Page 1 of 2). Service Reference Code Field DescriptionsField DescriptionS1Maintenance Package Source that produced the error code.0 Reserved1 Reserved2 POST, Firmware3 BIST4 Service Processor, base system controller, etc.5 Reserved8 Product specific service guide, MAPs9 ReservedA-F ReservedS2 Base classS3-S4 Sub-classS5 Unique version of the device/FRU type for a particular product.R1Device/FRU unique failure reason codes.1-7 Use in combination with R2, R3 for diagnostic test failure whenmaximum isolation was obtained.8-9 Use in combination with R2, R3 for diagnostic test failure whenmaximum isolation was NOT obtained.A Log analysis of POST error logB Log analysis of machine check or checkstop error logC ReservedD Diagnostic detected missing resourceE-F ReservedAppendix A. Interpreting Firmware Error Codes A-1
