Lately, my PowerBook has become narcoleptic. It goes to sleep even when it’s plugged in and I’ve been using it actively. Pressing a key usually wakes it up right away but not always.

I asked about this today on a Mac users’ mailing list that we have at work and someone mentioned that this a known problem with a faulty trackpad temperature sensor. The machine thinks it’s overheating so it goes to sleep. I can see evidence of this in my /var/log/system.log files:

Power Management received emergency overtemp signal. Going to sleep.

The above message appears in my logs 71 times!

Doing a search on this message, it seems that this problem is pretty common.