HP omnibook 4000 Service Manual

___________

44

The OmniBook 4000C and CT will not charge the batteries while in "ON"
mode.

Certain HP Vectra PCs will not link over I/R with the OB 4000.  Refer to the
technical newsletter for details.

The complete self-test procedure is documented in the OmniBook 4000
Operating Guide.

A note about interpreting self-test results.

Self-test alone should not be used to diagnose a hardware problem.  If the self-
test results are absolutely clear and repeatable, confirm the results with at least
two other non-self-test failure symptoms.

The OmniBook 4000 BIOS includes a POST facility that tests a number of
hardware and firmware items in the unit at each cold-start (BOOT or RESET).

These multiple beep codes indicate a failure in a simple test of:

a portion of base memory

Flash BIOS checksum

a portion of conventional memory

a portion of extended memory

If the unit fails to boot:

all accessories are removed, including memory cards, external floppy, port
expander, modems, PCMCIA cards, LAN cards, printers, VGA-out cables,
external pointing devices, clean AC power is provided (no "chained" battery
chargers or auto adapters), and press reset.

If the unit still fails to boot, it requires service.

Beep codes

Beep codes are used to identify a POST error that occurs when the screen is
not  available.  Once the screen is operating, diagnostic messages are
reported to the screen.  There are beep codes for both fatal and nonfatal
system board errors.