Power-On Self-Test; Table 3-4. Post Terminal-Error Beep Codes - HP Omnibook XE3 Service Manual

Power-On Self-Test

Note
If Quiet Boot is enabled in BIOS Setup (the default setting), press Esc during boot to see POST
messages.
The POST (power-on self-test) is a series of initialization routines and diagnostic tests that the system
BIOS runs when the notebook boots. The system BIOS will not boot the operating system if system
memory, the CPU, DMA, or the interrupt controller fails the POST diagnostic tests. POST progress is
indicated by a sequence of codes, and error messages are displayed if possible.
You should not necessarily interpret the failure of one or more POST tests as a hardware, software, or
firmware failure. If an error message appears, confirm the problem using other diagnostic tools. Not
all POST messages indicate a hardware, software, or firmware failure—some messages are for
information only.
First, confirm the failure by performing a "clean" boot: If the computer fails to restart with a clean
boot, it requires repair.
1. Remove all accessories, including SDRAM modules, PC cards, printer, external monitor, pointing
device, and keyboard.
2. Provide "clean" AC power—no auto adapter or unusual AC adapter configuration.
3. Press the system-off switch to return the notebook to a known state.
If the BIOS detects a terminal error condition, it halts POST after issuing a terminal error beep code
(see the following table). The beep code indicates the POST routine in which the terminal error
occurred.
Beep Codes*
1
1-2
1-2-2-3
1-3-1-1
1-3-1-3
1-3-4-1
1-3-4-3
1-4-1-1
2-1-2-3
2-2-3-1
1 long-2 short
1 long-5 short
* Up to four groups of short beeps, except as noted.
3-28 Troubleshooting and Diagnostics

Table 3-4. POST Terminal-Error Beep Codes

POST Description
One short beep before boot.
Search for option ROMs.
BIOS ROM checksum.
Test DRAM refresh.
Test NS87570 Keyboard Controller (part of motherboard).
RAM failure on address line xxxx.
RAM failure on data bits xxxx of low byte of memory bus.
RAM failure on data bits xxxx of high byte of memory bus.
Check ROM copyright notice.
Test for unexpected interrupts.
Improper video configuration (check video PCA DIP switches, replace video PCA)
or external ROM checksum failure.
Display DIP switches and EEPROM settings do not match (check DIP switch
settings).
HP Omnibook XE3 (Technology Codes GE and GD)