HP (Hewlett-Packard) 6100 Laptop User Manual


 
3-24 Troubleshooting and Diagnostics HP Omnibook 6000/6100
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 computer 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. First, confirm the failure by performing a “clean” boot:
Remove all accessories, including SDRAM modules, floppy drive, port replicator, PC Cards,
printer, external monitor, pointing device, and keyboard.
Provide “clean” AC power—no auto adapter or unusual AC adapter configuration.
Press the system-off switch to start the computer from a known state.
If the computer fails to boot with a clean boot, it requires repair. 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.
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.
Table 3-4. POST Terminal-Error Beep Codes
Beep Codes* POST Description
1 One short beep before boot.
1-2 Search for option ROMs.
1-2-2-3 BIOS ROM checksum.
1-3-1-1 Test DRAM refresh.
1-3-1-3 Test 8742 Keyboard Controller (part of power supply PCA).
1-3-4-1 RAM failure on address line xxxx.
1-3-4-3 RAM failure on data bits xxxx of low byte of memory bus.
1-4-1-1 RAM failure on data bits xxxx of high byte of memory bus.
2-1-2-3 Check ROM copyright notice.
2-2-3-1 Test for unexpected interrupts.
1 long-2 short Improper video configuration (check display DIP switches, replace display
interface PCA) or external ROM checksum failure.
1 long-5 short Display DIP switches and EEPROM settings do not match (check DIP switch
settings, reprogram EEPROM) (Omnibook 6000 only).
* Up to four groups of short beeps, except as noted.