iBook G4, 800 mhz sleeps at startup

[aztucson]

I have an iBook G4 (800 mhz, dual USB, 12.1 screen, OS X 10.4.11). When I try to power it on, I hear the chime, the screen comes on (I get the Apple logo w/ spinning wheel), then the login window which automatically logs me in, then the desktop. Immediately when the destop appears, I get a window saying my clock is set at March 24, 2001 and then the screen goes into a sleep mode. The light is pulsing near the release latch. It won't wake up.

I have zapped the PRAM (Apple-Option-P-R). I have also reset the PMU ? (Shift-Control-Option-Power) and this does shut off the power (the pulsing light goes off). I have also restarted the computer in open firmware (Apple-Option-O-F) and then typed:

reset-nvram (return)
set-defaults (return)
reset-all (return)

The problem is still the same with no improvement. I have done everything listed above with a good AC power adapter connected.

[djackmac]

That's a bad reed switch. You can unplug the reed switch from the logic board by removing the RAM door under the keyboard (should be a little white connector and red/green cable). Bad part about that is when you close the lid, the machine will not go to sleep. You will have to sleep the machine by clicking the Apple then select sleep. A replacement reed switch wouldn't be expensive but if you've never taken apart an ibook, I wouldn't recommend trying to replace it.