In article , mike wrote:
I have a Thinkpad 560 that won't power up.
The internal switcher chips are in shutdown mode.
The signal from the power switch ain't getting to the
power supply. The signal comes from a maze of unmarked
smt chips. I gave up tracing it to the connector and
went looking for visual clues.
The vias are not solder masked and don't appear to be plated.
There are several with some corrosion. I put wires thru the worst
ones. Now, the power supply will come up if I bend on the
main board just right.
I have no idea how to find open circuits on inner layers without
a schematic for reference.
The service manuals I downloaded from IBM are useless in this regard.
Is there a way to obtain the schematics for at least the power control
part of a Thinkpad 560? Even the pinout for the connector between the
main board and the power converter board would greatly simplify
the search.
I have run into this problem before. I had to replace the power control
board (I believe) with a unit I bought on Ebay. I tried for a while to
fix it, and believe it was an intermittant mechanical failure (maybe
via/internal trace), since it would work if I flexed it right.
These are nice machines, but had some problems. I think this is a common
problem. And yes, none of the vias are plated on the several TP560 models
I have owned.
Gotta be free cause this thing is gonna be
pretty much worthless even if I get it working. I just hate to see
it go to the landfill.
Yes, it's sad. I have a box full of old thinkpads and hate to throw
them away. When I have some time I want to see if I can get at least
one to work well from all of the broken ones.
Later, -ingo
Thanks, mike
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