
HP OmniBook 4100/4150 Troubleshooting and Diagnostics 3-5
If you can’t isolate the cause of a problem using the diagnostic tools, you can use the suggestions in
the following table to help find the problem.
Table 3-2. Troubleshooting Suggestions
Symptom Call Center:
Suggestions
Repair Center:
Likely Causes
Repair Center:
Comments
To help determine likely causes, check to see what replaceable modules are involved in the system function and
what roles they play. See the table on page 1-15.
Startup
Does not boot on
ac or battery
Check the power source.
Push system-off button.
Unplug the ac adapter and
remove all batteries, then
reconnect power.
Remove any RAM board and
try again. Reinsert and try
again.
AC adapter.
DC-DC PCA.
RAM board.
CPU module.
Motherboard.
VGA PCA.
LCD module.
Hard drive.
For an OmniBook 4100 with
serial number below
TW84099999, check CPU
bottom plate. If plate is less
than “Rev 4”, replace bottom
plate. Also, make sure a
square spacer is installed on
top of the CPU top plate at
the right-rear corner. (Service
note 4100-03C.)
Check ac adapter. Remove
any RAM boards and retry.
If power status light does not
turn on, reprogram BIOS,
replace DC-DC PCA, replace
motherboard.
If power status light turns on
but display remains off, try
external monitor. If monitor
shows successful boot,
replace LCD module. If
monitor shows activity but
BIOS does not complete,
replace CPU module. If
monitor is blank, replace
VGA PCA, replace CPU
module, replace
motherboard.
If power status light and
display turn on, BIOS
completes, but OS does not
start from hard disk or from
floppy drive, replace CPU
module, then motherboard. If
OS starts from floppy drive,
reload hard drive, replace
hard drive.
OmniBook 4150
Series model beeps
once, spins hard
disk, repeats, but
does not boot
RAM board (OB 4150
Series).
Make sure at least one RAM
board is installed.
Does not boot on
battery (boots on
ac)
Check battery level on
battery LEDs.
Check battery contacts. If
available, try another battery.
Battery or contacts.
DC-DC PCA.
Motherboard.