PowerBook G4 1.67GHz won’t start...any experts here?

[marqus]

Hi there,

I just got an A1138 G4 Powerbook that won’t do anything when pushing the power button.
The battery seems to be dead. The 65W PSU shows permanent orange light, never green.
I tore it apart, checked every cable, had the LB removed completely. Could not see any faulty spot so far. The thing is, I do not know where to look or what to check in the 1st place. So I am looking at it like a monkey in clock works.

Is there any suggestion how to breath life back into this top of the line PowerBook? Where to start?

thx
Markus

 

[Raging Dufus]

The DC-in and sound board is a known weakness of the later Aluminum PowerBooks. If you have no reason to suspect the logic board has gone bad, or that your power adapter has gone bad, then it's almost certainly that power/sound board (it's one piece that serves both functions). You should be able to find the part on eBay (take a look at the one you have, to make sure you match the part number), and iFixit has a great guide to replace it:

PowerBook G4 Aluminum 15" 1.67 GHz DC & Sound Card Replacement

This guide will show you how to replace the DC & Sound Card on your PowerBook.

www.ifixit.com

 

[micahgartman]

Click on the link in my signature and find your PowerBook in the list.

Look for "Power Button pads on logic board" in the troubleshooting section.

If that doesn't work, disconnect the PRAM battery and try again.

 

[marqus]

thx. 1st tip did not change anything, found the pads though. But please, where is the PRAM battery ???

Ah, found it. wrapped in aluminium on top of the DVD.

No change. Damn.

will try to use the heat gun on my DC board

Found out, that the connector cable leading from DC board to Main-Logic board got 20 Volts. So there is voltage coming to the LB. But from there on, I dont know the way...

 

[micahgartman]

thx. 1st tip did not change anything, found the pads though. But please, where is the PRAM battery ???

It's taped to the top of the CD drive. It's also referred to as the "backup battery."

 

[marqus]

It's taped to the top of the CD drive. It's also referred to as the "backup battery."

Still, as you see above, no change. I think its dead.

 

[micahgartman]

My condolences

R.I.P., little PowerBook.

 

[marqus]

Do you know how the current runs through the book after arriving on the socket?

 

[micahgartman]

I'm afraid not. But, you can search Google for "a1138 schematic" and find what you're looking for.