|
|
If you like this site, please support us by spreading
the word.
We have made it easy to let your friends know about
us. Just click on the Recommend-It icon below.
|
|
|
POST Error Beep Codes
|
|
Every time a computer is switched on it performs a short diagnostic routine
known as the POST, or Power On Self Test. The POST is a small program contained in the BIOS. It checks that basic
hardware is present and performs a rudimentary memory test. The POST announces the results of its routine both
audibly (a series of beeps on the PC speaker) and visually (displaying a brief summary or codes on the screen).
The audible method is essential since a fault may exist with the graphics
card or monitor. If all is well, the computer typically emits a single beep and carries on booting. The number
and duration of the beeps is intended as a coded message and understanding them will allow you to diagnose any
problems the computer may have.
The codes vary according to the manufacturer of the BIOS. Here are some
of the more common codes:
AMI I Award I IBM I Phoenix
|
|
AMI BIOS
|
|
Number and Duration of Beeps
|
Message
|
| one short |
DRAM refresh failure (Problem with memory) |
| two short |
Parity circuit failure |
| three short |
Base 64K RAM failure |
| four short |
System Timer failure |
| five short |
Processor failure |
| six short |
Keyboard Controller / Gate A20 failure |
| seven short |
Virtual Mode Exception error |
| eight short |
Display Memory Read/Write failure (fault with video card) |
| nine short |
ROM BIOS Checksum error (fault with BIOS chip) |
| ten short |
CMOS Shutdown Read/Write error |
| eleven short |
Cache memory |
| one long |
Passed (no errors) |
| one long, two short |
Video failure |
| one long, three short |
Base / Extended Memory failure |
| one long, eight short |
Display / Retrace Test failure |
|
Award BIOS
|
|
Number and Duration of Beeps
|
Message
|
| one short |
Passed (no errors) |
| two short |
Any non-fatal error |
| one long, two short |
Video failure |
| one long, three short |
Keyboard Controller failure (applies to 286, 386 and 486) |
|
IBM BIOS
|
|
Number and Duration of Beeps
|
Message
|
| none |
Power Supply or System Board failure (possible short) |
| one short |
Passed (no errors) |
| one short (blank screen) |
Video error (check cable) |
| one short (no boot) |
Floppy Drive error |
| two short |
Configuration Error (displayed on screen) |
| repeating short |
Power Supply or System Board failure |
| continuous |
Power Supply or System Board / Keyboard stuck |
| one long, one short |
System Board failure |
| one long, two short |
Video (Mono/CGA) failure (check cable) |
| one long, three short |
Video (EGA) failure (check cable) |
| three long |
Keyboard Card error |
|
Phoenix BIOS
|
|
Number of Beeps
|
Message
|
| one, one, three |
CMOS Read/Write |
| one, one, four |
ROM BIOS Checksum failure |
| one, two, one |
Programmable Interval Timer failure |
| one, two, two |
DMA Initialisation failure |
| one, two, three |
DMA Page Register Read/Write failure |
| one, three, one |
RAM Refresh Verification error |
| one, three, three |
First 64K RAM Chip/Data Line failure |
| one, three, four |
First 64K RAM Odd/Even Logic |
| one, four, one |
First 64K RAM: Address Line |
| one, four, two |
First 64K RAM: Parity failure |
| one, four, three |
Fail-Safe Timer Feature (EISA only) |
| one, four, four |
Software NMI Port failure (EISA only) |
| two (followed by various combinations) |
First 64K RAM Chip/Data Line failure (combinations indicate which bit) |
| three, one, one |
Slave DMA Register failure |
| three, one, two |
Master DMA Register failure |
| three, one, three |
Master Interrupt Mask Register failure |
| three, one, four |
Slave Interrupt Mask Register failure |
| three, two, four |
Keyboard Controller failure |
| three, three, four |
Display Memory failure |
| three, four, one |
Display Retrace failure |
| three, four, two |
Video ROM search proceeding |
| four, two, one |
Timer Tick failure |
| four, two, two |
Shutdown failure |
| four, two, three |
Gate A20 failure |
| four, two, four |
Unexpected Interrupt in Protected Mode |
| four, three, one |
RAM test above 64K failure |
| four, three, two/three |
Programmable Interval Timer, Channel 2 failure |
| four, three, four |
Realtime Clock failure |
| four, four, one |
Serial Port error |
| four, four, two |
Parallel Port error |
| four, four, three |
Math Co-processor failure |
| (tone) one, one, two |
System Board Select |
| (tone) one, one, three |
Extender CMOS RAM |
|
