PowerBook 270c

[digitalrampage]

Hi Everyone,

My Powerbook 270c wasn't working and ticking, so I cracked it open and saw that the caps were leaking. Removed all the SMD caps, cleaned and replaced with Tantalum.

There was no change. So I washed the whole board and the unit still is not powering up with this buzzing from the cap area.

Any suggestions on possible other causes?

 

[techknight]

there may be shorted semiconductors in that area. you will need to do some electronics troubleshooting to figure it out. 

 

[digitalrampage]

there may be shorted semiconductors in that area. you will need to do some electronics troubleshooting to figure it out. 

I don't want to sound like a dullard/luddite, but what kind of troubleshooting can you recommend. Visually everything checks out, do I start looking for shorts to ground?

 

[techknight]

you could start there. Too bad you dont have a 2nd board that works as a reference. Thats what I tend to do with machines that I have no schematics for.