Toshiba laptop & lightning strike

  • Thread starter Thread starter TeGGeR®
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TeGGeR®

I've been given a Toshiba Satellite A30 laptop that was damaged when a
lightning bolt hit someone's house. This thing was plugged into a DSL modem
and the 110V wall outlet. There was a cheap "surge suppressor" in the line
from the wall.

I've already determined that the power transfromer (the thing that converts
110VAC to 19VDC) is dead. When a good transformer is plugged in, the smell
of magic smoke is immediately evident. There is no sign of activity from
the laptop.

The owner has decided to buy a new laptop, and I've been given this one
just in case it can be made to work again.

So, my questions: Based on the description above, is there any way to
predict how far in the power spike went? What's most likely to be damaged?
 
To damage, electricity must have both an incoming and
outgoing path. You can suspect at least one path - the power
line and 19 V transformer. A possible outgoing path may be
through DSL. Trace everything in that path. It should
include all damaged parts, parts that may have been
overstressed, and parts that conducted the transient but were
not damaged.

Typically, an incoming and destructive transient is from AC
mains. Outgoing is often via phone line because the telco
installs a 'whole house' type protector, connected to earth
ground, for free. 'Whole house' type protectors being that
inexpensive and that effective.

That 'cheap' surge suppressor could have provided a
transient with more destructive paths into the computer. IOW
adjacent protectors can even make damage of adjacent
transistors easier.

A most probable reason for laptop damage was no effective
'whole house' protector on AC mains. Effective protector
makes a 'less than 10 foot' connection to earth ground. No
properly earthed AC mains protector would be why AC mains was
an incoming path - to find earth ground destructively via DSL
port.
 
w_tom said:
:



To damage, electricity must have both an incoming and
outgoing path. You can suspect at least one path - the power
line and 19 V transformer. A possible outgoing path may be
through DSL. Trace everything in that path.
Click to expand...

<snip>


Thanks, but I asked WHAT was likely damaged, not HOW.

Since nobody here seems to know, I'll have to look elsewhere for how to
determine that on my own.

I fear the voltage spike has gone past the power supply and damaged the
motherboard, but have no way of knowing that now. Worst case, I'll pay
somebody to figure that out, then go from there.

Thanks anyway.
 
I've already determined that the power transfromer (the thing that converts
110VAC to 19VDC) is dead. When a good transformer is plugged in, the smell
of magic smoke is immediately evident. There is no sign of activity from
Click to expand...

This wasn't wise.
So, my questions: Based on the description above, is there any way to
predict how far in the power spike went? What's most likely to be damaged?
Click to expand...

It's most likely that various semiconductors in the power supply
section of the device have failed short-circuit, which is a typical
failure mode. When you plugged in a good adapter, you crowbarred 19VDC
across something that wasn't expecting it, and that something fried.

If this machine happens to bring the DC/DC conversion onto a separate
board, and you're a real gambler, you could try replacing that DC/DC
board; I'd say you've got about 5% chance this would fix it. However,
forget about trying to repair this at a component level. Even if there
was just one fried transistor, you will have great difficulty simply
identifying what the part number is to buy a replacement, because they
are all cryptically marked (not uniquely marked) SMDs. Schematics are
not obtainable, and it's practically impossible to trace out these
ten-layer boards.

The DSL plugged in means it's likely your Ethernet or USB got a nice
zap, which may or may not have made it through to the expensive digital
stuff like the CPU and RAM.

Buy a new motherboard (still no guarantee, since the processor and
peripherals may be toast) or part the machine out. The LCD, hard drive,
optical drive are probably still good. Processor and RAM are maybes but
I'd bet on them still being OK.
 
'How' is necessary to answer your question. Without how,
then no respondant has sufficient information. The above
answer goes even farther. It lists specific components that
were probably in that electrical path. This from someone who
literally takes lightning damaged parts, identifies the
damaged components, replaces those components, and uses the
now repaired part for years without failure. You will not get
a better source for your answer. It is the best answer
available since the newsgroup was provided minimal
information.

Another answer is speculation - try this and try that. It
could be this or it could be that. When done, you might
replace half the machine and still not have a working laptop.
Without HOW, then no one can answer WHAT.
 
w_tom said:
'How' is necessary to answer your question. Without how,
then no respondant has sufficient information. The above
answer goes even farther. It lists specific components that
were probably in that electrical path.
Click to expand...



Not hard to figure out, I'd think. Power supply, motherboard, PCI bus,
associated miscellanea.


This from someone who
literally takes lightning damaged parts, identifies the
damaged components, replaces those components, and uses the
now repaired part for years without failure.
Click to expand...



And you can't tell me how likely it is that the damage goes past the power
supply, and how often you see the PCI bus damaged through the modem when
the modem has another device between it and the wall?

You must see patterns in your work, surely?


You will not get
a better source for your answer. It is the best answer
available since the newsgroup was provided minimal
information.

Another answer is speculation - try this and try that.
Click to expand...



I am in the middle of disassembling the laptop. Just for fun, of course,
since I know next to nothing about laptops and wish to learn what I can
from the cadaver. I am currently confounded by tiny Torx screws that hold
the power supply in place. They are of a size my local hardware store does
not stock. 10? 5? I only have a driver as small as 15.


It
could be this or it could be that. When done, you might
replace half the machine and still not have a working laptop.
Without HOW, then no one can answer WHAT.
Click to expand...


It will remain unworking. My current project is to hook the now excised
hard drive up to a desktop (with the appropriate adapter of course) to see
if it can be read, in order to recover such data as may be recovered.

Thanks for your help.
 
Not hard to figure out, I'd think. Power supply, motherboard, PCI bus,
associated miscellanea.
Click to expand...

If it weren't, you'd already know, yes?

It can travel arcross many areas, but the magnitude and
duration may determine what damage was actually done, as
well as the specific design this particular system had. We
cannot supply some kind of cheat-sheet that would apply to
one specific system as a rule.

You should test the internal power board. If it works,
replace the motherboard. If it doesn't, replace it, then
test the motherboard (try whole system). At that point you
will have a laborious process of testing every minute detail
of system operation.


There is no shortcut, no use in presumptions about limit to
damages... whole thing needs checked in a systematic fashion
from a stripped-down and then gradually re-integrated (parts
readded) state.
 
It might be more useful to suggest what might not be damaged that still
has resale value:

-Keyboard
-Hard drive (maybe)
-LCD panel (maybe)
-Inverter (maybe)
-Optical drive (maybe)
-Battery
-Case and Plastics

If the hard drive is ok, then probably so is the LCD panel and the
optical drive. That would probably suggest that the surge didn't get
beyond the motherboard.
 
To take what Kony has posted farther. Unlike desktop
computers, laptops are more uniquely designed. What happened
to that Toshiba requires details not provided here. And so
you were provided a probably path of destruction; incomong in
AC mains and outgoing on DSL port. Using that, you now have a
first path to look for an incoming / outgoing path.

Computers already have internal protection. For example,
galvanic protection inside the power supply had to be
overwhelmed to have suffered damage. OK. But still the reason
why it was overwhelmed - what the transient was seeking - also
helps to identify what may be damaged in that power supply and
on various boards inside the laptop.

Your list of suspects assumed something is damaged when
transient is only incoming. For example, why would PCI bus or
motherboard be damaged? In desktop machines, ae modem is
often damaged by a transient from AC mains. To get to modem,
the transient used PCI bus connector and motherboard traces.
And yet no damage to PCI bus electronics nor motherboard
occurs. Again, if we follow the path through that desktop
machine, then path through PCI bus and motherboard does not
pass through any electronics. It would be extremely
difficult, using your assumptions, to discover what was and
was not damaged.

Don't think for one minute that you will see a damaged
part. Most damaged devices have no external indication. Just
another reason why it is so helpful to know what the outgoing
transient path was. Of course, little will be learned without
a volt meter. One of the first things to test is power from
battery, through power supply board, to computer. Where does
voltage exist and not exist? Your eyes will not see damage.
To see damage means eyes that can see those details. The best
tool per dollar is a 3.5 digit multimeter.

Dissembling is how one learns. One never saves money by
repairing things. But the value is obtained in doing the work
- and learning.

Torx is another example. #10 Torx is a most common size
that any properly stocked hardware store should carry. Even
Sears carries torx drivers (last I saw before the latest
restructuring) of even odder sizes such as 8 and 9.
 
If it weren't, you'd already know, yes?
Click to expand...




It looks like the hard drive is OK. I was able to read it on a desktop and
extract the necessary files.


It can travel arcross many areas, but the magnitude and
duration may determine what damage was actually done, as
well as the specific design this particular system had. We
cannot supply some kind of cheat-sheet that would apply to
one specific system as a rule.

You should test the internal power board. If it works,
replace the motherboard.
Click to expand...



I need to get my hands on a power board first.



If it doesn't, replace it, then
test the motherboard (try whole system). At that point you
will have a laborious process of testing every minute detail
of system operation.


There is no shortcut, no use in presumptions about limit to
damages... whole thing needs checked in a systematic fashion
from a stripped-down and then gradually re-integrated (parts
readded) state.
Click to expand...


Once I find a power board, I can do that.
 
Torx is another example. #10 Torx is a most common size
that any properly stocked hardware store should carry. Even
Sears carries torx drivers (last I saw before the latest
restructuring) of even odder sizes such as 8 and 9.
Click to expand...


My hardware store has nothing so small as these. I'll check out Sears.
 
Unique means one only, so there can't be degrees of uniqueness.
Click to expand...

Only in a simplistic view.
A laptop is not one singular design, it is many subsystems
with a certain level of modularity, each of which may vary
in their individual uniqueness but are still but a part of
the whole.
 
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