Powerbook Forced Sleep Through Overheating

[jl2704]

My 15" 1.5 Ghz Powebook has been on the blink lately.
Two days ago, it might have to deal with the latest NYC heat wave, had started to suddenly go into sleep mode.
After reading through the system log files via Onyx, I discovered this:

mergency overtemp signal. Going to sleep.
Aug 3 15:25:38 jl2704s-powerbook-g4-15 kernel[0]: AirPort: Link DOWN (Client disAssoc 0)
Aug 3 15:25:38 jl2704s-powerbook-g4-15 kernel[0]: Power Management received emergency overtemp signal. Going to sleep.
Aug 3 15:25:38 jl2704s-powerbook-g4-15 launchd: Server 0 in bootstrap 1103 uid 0: "/usr/sbin/lookupd"[153]: exited abnormally: Hangup
Aug 3 15:25:38 jl2704s-powerbook-g4-15 configd[34]: posting notification com.apple.system.config.network_change
Aug 3 15:25:38 jl2704s-powerbook-g4-15 configd[34]: setting hostname to "jl2704s-powerbook-g4-15.local"
Aug 3 15:25:40 jl2704s-powerbook-g4-15 kernel[0]: IOUSBWorkLoop::closeGate - interrupt Thread being held offPower Management received emergency overtemp signal. Going to sleep.
Aug 3 15:25:41 jl2704s-powerbook-g4-15 kernel[0]: Power Management received emergency overtemp signal. Going to sleep.
Aug 3 15:25:55 jl2704s-powerbook-g4-15 kernel[0]: Power Management received emergency overtemp signal. Going to sleep.System Sleep
Aug 3 15:25:55 jl2704s-powerbook-g4-15 kernel[0]:

a whole series of messages like this in systemlog.

Unfortunately, there is no indication whatsoever that my laptop which is only moderately warm to the touch is overheating.

What am I supposed to do?
I had bought this powerbook in July 05 and the one year warranty had expired.
Will repair costs be substantial?

 

[matthewpfritz]

I believe there is a faulty temp sensor (probably for the Track Pad) that is sending an erroneous overtemp condition. I've experienced the same problem with my 17" G4. Apple tech had me shut down, remove the battery and power supply, then hold down the power key for 5 seconds. That resets the Power Management unit. This gave me 24 hours without the problem, but it has now returned. I've tried numerous tricks to no avail. I'll be sending mine in this week for repair. Luckily, I have Apple Care through work... I don't know what it would cost to fix, but certainly cheaper than a new machine! Good luck!

Matt