18 - PowerBook G4 (15-inch FW800) Troubleshooting Hardware Symptom Charts

Computer beeps twice at startup

1. Two beeps means that EDO memory is installed in the RAM expansion slot. The
PowerBook does not accept EDO memory.
2. Replace RAM card(s) with known-good and compatible RAM and restart.
If symptom repeats, replace logic board.

Computer beeps three times at startup

1. Three beeps means that no RAM banks passed memory testing.
2. If a RAM card is installed in the upper expansion slot (if not, skip to next step), remove
it and restart.
If symptom does not repeat, replace RAM card.
If symptom repeats, replace RAM in lower RAM slot with known-good and
compatible RAM card and restart. If symptom repeats, replace logic board.
3. If a RAM card is not installed in the upper expansion slot, replace RAM in lower RAM
slot with known-good and compatible RAM card and restart.
If symptom repeats, replace logic board.

Computer beeps four times at startup

1. Four beeps indicates a bad checksum for the remainder of the boot ROM. The ROM
(which is located on the logic board) is bad.
2. Replace RAM card(s) with known-good and compatible RAM and restart.
If symptom repeats, replace logic board.
Related Knowledge Base articles:
58442: Power On Self-Test Beep Definition - Part 2
95132: PowerBook G4: Installing or Replacing Memory