I upgrated a PB 12" 1.5Ghz from 10.5.6 to 10.5.8 and after the update the fan was running high speed. Don't know if it's a coincidence, a software problem related to the update or a hardware problem. Did you made a software update too ?

[quote|lemerise]I upgrated a PB 12" 1.5Ghz from 10.5.6 to 10.5.8 and after the update the fan was running high speed. Don't know if it's a coincidence, a software problem related to the update or a hardware problem. Did you made a software update too ?[/quote]

Thanks for your reply. Has nothing to do with software. The fan starts running immediately as I press the power button, before even the software is loaded. I use the same version of OS X (Leopard) as before I replace the disk.

[quote|tos070]Thanks for your reply. Has nothing to do with software. The fan starts running immediately as I press the power button, before even the software is loaded. I use the same version of OS X (Leopard) as before I replace the disk.[/quote]

Quote from lemerise:

I upgrated a PB 12" 1.5Ghz from 10.5.6 to 10.5.8 and after the update the fan was running high speed. Don't know if it's a coincidence, a software problem related to the update or a hardware problem. Did you made a software update too ?

The fan starts at high speed even before the chimes sound!

I am wondering whether something is wrong with the heat sink, although I did not remove that one, and it somehow does not touch the processor anymore, which results to (instantly??) high temperature of the processor and increased fan speed. But still, it is weird that the fan starts running immediately when pressing the on button.

[quote|tos070]The fan starts at high speed even before the chimes sound! I am wondering whether something is wrong with the heat sink, although I did not remove that one, and it somehow does not touch the processor anymore, which results to (instantly??) high temperature of the processor and increased fan speed. But still, it is weird that the fan starts running immediately when pressing the on button.[/quote]

Could be a small cable disconnected near the power light.

OR

Known issue: "the whirring fan of death"

Small ic on the logic board loosens, you would have to be re-ball the logic board to fix. To see if this broken piece is the problem you put pressure, sometimes a LOT of pressure, on the palm rest to the left of the mouse and try to startup. If it starts up, then dies within seconds of removing your palm, your logic board is the problem.

Good Luck,

N

[quote|machead3]Could be '''a small cable disconnected near the power light. ''' OR '''Known issue:''' ''"the whirring fan of death"'' Small ic on the logic board loosens, you would have to be re-ball the logic board to fix. To see if this broken piece is the problem you ''put pressure,''' sometimes a LOT of pressure,''' on the palm rest to the left of the mouse'' and try to startup. If it starts up, then dies within seconds of removing your palm, your logic board is the problem. Good Luck, N[/quote]

Quote from tos070:

The fan starts at high speed even before the chimes sound!

If the fan start even when the PB is cold then I don't think it could be a heat problem related to the heatsink. Could be the heat sensor. Could you download iStat and check the fan and temperature readings ?

http://www.islayer.com/apps/istatmenus/

[quote|lemerise]If the fan start even when the PB is cold then I don't think it could be a heat problem related to the heatsink. Could be the heat sensor. Could you download iStat and check the fan and temperature readings ? http://www.islayer.com/apps/istatmenus/[/quote]

Quote from machead3:

Could be a small cable disconnected near the power light.

OR

Known issue: "the whirring fan of death"

Small ic on the logic board loosens, you would have to be re-ball the logic board to fix. To see if this broken piece is the problem you put pressure, sometimes a LOT of pressure, on the palm rest to the left of the mouse and try to startup. If it starts up, then dies within seconds of removing your palm, your logic board is the problem.

N

I am not sure what you mean with "power light". The on/off button? Or the button you press to unlock the display? Could you maybe specify by means of a photo from the ifixit repair (e.g. photo nr 34 by repair "replacement hard disk") or so.

I put pressure on the palm rest to the left of the trackpad, but didn't solve the problem :-(

[quote|tos070]I am not sure what you mean with "power light". The on/off button? Or the button you press to unlock the display? Could you maybe specify by means of a photo from the ifixit repair (e.g. photo nr 34 by repair "replacement hard disk") or so. I put pressure on the palm rest to the left of the trackpad, but didn't solve the problem :-([/quote]

Quote from lemerise:

If the fan start even when the PB is cold then I don't think it could be a heat problem related to the heatsink. Could be the heat sensor. Could you download iStat and check the fan and temperature readings ?

http://www.islayer.com/apps/istatmenus/

graphics processor die=36.8 C

Hard disk drive bottomside=27C

Processor Topside=29.5C

[quote|tos070]graphics processor die=36.8 C Hard disk drive bottomside=27C Processor Topside=29.5C[/quote]

Hum...temperature readings seems good. The PB is not overheating. Could you boot the machine with another system (installation disk, external drive) just to check if the problem could be software related ?

[quote|lemerise]Hum...temperature readings seems good. The PB is not overheating. Could you boot the machine with another system (installation disk, external drive) just to check if the problem could be software related ?[/quote]

Quote from lemerise:

Hum...temperature readings seems good. The PB is not overheating. Could you boot the machine with another system (installation disk, external drive) just to check if the problem could be software related ?

I boot with the installation disk, same problem. The moment I press the on/off button fan starts. To me it seems like a connector which does not fit well, but I've checked them all and can't see what's wrong. I am not sure which connectors machead3 meant.

[quote|tos070]I boot with the installation disk, same problem. The moment I press the on/off button fan starts. To me it seems like a connector which does not fit well, but I've checked them all and can't see what's wrong. I am not sure which connectors machead3 meant.[/quote]

I made many logic board swap in the PB 12" 1.33/1.5 models and don't remember any sensors connectors on the logic board. They could be integrated to the board. I would suspect the HD sensor even if the reading is good since you only worked in the HD area when you swapped the disk.

[quote|lemerise]I made many logic board swap in the PB 12" 1.33/1.5 models and don't remember any sensors connectors on the logic board. They could be integrated to the board. I would suspect the HD sensor even if the reading is good since you only worked in the HD area when you swapped the disk.[/quote]

The strange thing is that the problem is present also when I replace the new disk with the old one!

[quote|tos070]The strange thing is that the problem is present also when I replace the new disk with the old one![/quote]

Yes then the sensor should be under the disk on the logic board cause iStat says:

Hard disk drive bottomside=27C

Maybe someone here will have a better knowledge than me about this PB model sensors.

[quote|lemerise]Yes then the sensor should be under the disk on the logic board cause iStat says: Hard disk drive bottomside=27C Maybe someone here will have a better knowledge than me about this PB model sensors.[/quote]

I am having a similar problem. Also suspected heat problems but it does start sometimes and when in a very cold room i managed to reinstall OSX.

I have taken it all apart and reapplied new pasta on the heatsinks without any difference.

When it does start it works for about 10 minutes, and then slows down to eventually come to a halt.

Temperature monitor says around 34-39C and if opening a heavy webpage it goes over 40C and usually freezes.

I have gotten this powerbook G4 17" 1,67GHz for free since it didn't work properly and i am very eager to fix it.

Anyone found a solution yet, or is it hardware?

[quote|Patrik]I am having a similar problem. Also suspected heat problems but it does start sometimes and when in a very cold room i managed to reinstall OSX. I have taken it all apart and reapplied new pasta on the heatsinks without any difference. When it does start it works for about 10 minutes, and then slows down to eventually come to a halt. Temperature monitor says around 34-39C and if opening a heavy webpage it goes over 40C and usually freezes. I have gotten this powerbook G4 17" 1,67GHz for free since it didn't work properly and i am very eager to fix it. Anyone found a solution yet, or is it hardware?[/quote]