"Jeff Liebermann" skrev i en meddelelse
...
Here's one I haven't seen befo
http://802.11junk.com/jeffl/crud/toshiba-rot-02.jpg
It's the motherboard from a Toshiba Satellite Pro M15-S405 laptop. The
brown crud is probably flux left over from the soldering operation or
something corrosive, that was trapped between the PCB and a thin
plastic "protective" covering under the DVD drive. The board acts
totally dead. No power, no charge lite, no sounds, no nothing. At
first, I thought that someone had spilled some liquid into the laptop.
Nope, because all the corrosion is BETWEEN the PCB and the plastic,
with nothing on top of the plastic. The plastic covering was totally
clean. There's no corrosion in the area that's NOT under the
"protective" covering, so it seems whatever did the damage, was
volatile.

The customer has 3 other identical laptops. I just inspected them
(through the DVD slot), and found no corrosion.

I'm not sure I'll be able to fix this one as the rotted traces in this
area are very tiny. It's probably not worth the effort for a 9 year
old laptop.

From what I can see the PCB is flipped over (upside down).
Liquid (cola?) might have landed on the top surface and then it is wicked
through the PCB through the via's to the bottom side where it gets trapped
in between the PCB and the plastic covering.
Have seen almost the same with a Logitech keyboard.
The liquid that landed on the top surface was free to evaporate.
The liquid on the bottom surface was trapped and could etch away :-(



--
Uffe Bærentsen