IBM's Original POST codes

Post diagnostic errors ( many are IBM PC/XT only and could vary from one system to another)

• 01x - Unknown Error
• 02x - Power supply
• 1xx - System motherboard error
• 161, Dead CMOS battery
• 2xx - Memory failure
• 3xx - Keyboard failure
• 4xx - Monochrome display adapter failure (video card error codes)
• 5xx - CGA (Color Graphics Adapter) display adapter failure
• 6xx - Floppy drive
• 7xx - Math co-processor error
• 8xx -
• 9xx - Parallel Printer port error
• 10xx - Second parallel printer port error
• 11xx - Serial Port error
• 12xx - Second serial port error
• 13xx - Game port adapter
• 14xx - Printer control
• 15xx - SDLC adapter
• 16xx - display emulator cards
• 17xx - Hard Drive
  • 1701, POST failure of hard drive - ...Hard Drive Troubleshooting
  • 1702, Hard Drive Adapter Card error
  • 1703, Hard Drive failure
  • 1704, Hard Drive OR Adapter failure
  • 1780, Hard drive 0 failed
  • 1781, Hard drive 1 failed
  • 1782, Hard drive controler failed
  • 1790, Hard drive 0 error
  • 1791, Hard drive 1 error
• 18xx - I/O card error
• 19xx - 3270 card errors
• 20xx - BSC adapter
• 21xx - BSC adapter
• 22xx -
• 23xx -
• 24xx - EGA video card error, VGA error
• 25xx -
• 26xx -
• 27xx -
• 28xx -
• 29xx -
• 30xx - Network card error
• 31xx - Network card error
• 32xx -
• 33xx -
• 34xx -
• 35xx -
• 36xx -
• 74xx - VGA card
• 1xx, System Motherboard Errors
• 104xxx - ESDI hard drive error
• 101, Interrupt failure
• 102, Timer Failure
• 103, Timer Interrupt Failure
• 104, Protected mode failure
• 105, 8042 command error