Flakey LCD display on PowerBook
 

The display on my four-year-old Powerbook G3/FireWire (Pismo) is
starting to flake out. It's had the usual regional dimness for a while,
mostly the lower-left corner, and I assume that's the CCL bulb. However,
now there's something digital going on. It manifests itself in
shimmering red areas extending to the right of strongly-colored areas,
as well as a general zebra-effect with every other column of pixels
getting dim. (Oddly, I never have trouble reading my usual thin black
text on white background.)

To temporarily fix it, all I have to do is to squeeze the screen at a
point about 1" below the top and 4" from the left edge. Sometimes it
works for a while, other times it immediately returns, but the squeeze
always fixes it again.

I've opened up the computer, and the panel is a Samsung LT141X7-124. My
pressure point is right where the cable from the motherboard plugs into
the display. However, I played with the connection and couldn't get it
to fail, so I'm guessing that's not it. There are also wide areas of
traces going to the edge of the display, presumably to the lines
controlling the actual LCD cells, and my guess is that some of those
aren't making complete contact.

So, questions:

- Assuming it is NOT the main display connector, is this something I'm
likely to be able to fix?

- If I can't fix it, any suggestions as to model number and source of
LCD panel to replace it? (The cable to the display is designed for that
connector placement, so the form factor must be the same.)


Thanks,
Dan

--
Daniel T. Griscom Work: (781) 665-0053
Suitable Systems Fax: (781) 665-7106
152 Cochrane Street
Melrose, MA 02176-1433 http://www.suitable.com/

This is serviced by replacing the panel assembly and the cable. You will
have to find out who the Pismo support is, and send your computer to them
for service. I don't think they will sell you the parts to service this
yourself, but you can try. Look in your instruction manual, or visit their
web page to have their service details.

The display panels commonly fail on most laptops from the handling action,
and folding the panel up and down all the time. If for example, the panel
was left in the up position all the time, and rarely handled, it would most
likely take much longer, or never fail like this. I have some clients were
we have to send out their laptop about once a year, because of the excessive
handling. Each time the display panel is folded up and down, there are
stresses on the panel, the ribbon cable, the connectors, and the hinges on
the case.

--

Jerry G.
======


"Daniel Griscom" wrote in message
...
The display on my four-year-old Powerbook G3/FireWire (Pismo) is
starting to flake out. It's had the usual regional dimness for a while,
mostly the lower-left corner, and I assume that's the CCL bulb. However,
now there's something digital going on. It manifests itself in
shimmering red areas extending to the right of strongly-colored areas,
as well as a general zebra-effect with every other column of pixels
getting dim. (Oddly, I never have trouble reading my usual thin black
text on white background.)

To temporarily fix it, all I have to do is to squeeze the screen at a
point about 1" below the top and 4" from the left edge. Sometimes it
works for a while, other times it immediately returns, but the squeeze
always fixes it again.

I've opened up the computer, and the panel is a Samsung LT141X7-124. My
pressure point is right where the cable from the motherboard plugs into
the display. However, I played with the connection and couldn't get it
to fail, so I'm guessing that's not it. There are also wide areas of
traces going to the edge of the display, presumably to the lines
controlling the actual LCD cells, and my guess is that some of those
aren't making complete contact.

So, questions:

- Assuming it is NOT the main display connector, is this something I'm
likely to be able to fix?

- If I can't fix it, any suggestions as to model number and source of
LCD panel to replace it? (The cable to the display is designed for that
connector placement, so the form factor must be the same.)


Thanks,
Dan

--
Daniel T. Griscom Work: (781) 665-0053
Suitable Systems Fax: (781) 665-7106
152 Cochrane Street
Melrose, MA 02176-1433 http://www.suitable.com/

In article ,
"Jerry G." wrote:

To: "Jerry G."
From: Daniel Griscom
Subject: Flakey LCD display on PowerBook
Cc:
Bcc:
X-Attachments:

At 11:14 AM -0500 1/4/05, Jerry G. wrote:
This is serviced by replacing the panel assembly and the cable. You will
have to find out who the Pismo support is, and send your computer to them
for service. I don't think they will sell you the parts to service this
yourself, but you can try. Look in your instruction manual, or visit their
web page to have their service details.

Thanks. It's an Apple product, and I'm pretty sure they no longer
service it. There's a number of third-party companies that do the
service, but prices range from $300-$500, and I'm hoping to avoid that.

The display panels commonly fail on most laptops from the handling action,
and folding the panel up and down all the time. If for example, the panel
was left in the up position all the time, and rarely handled, it would most
likely take much longer, or never fail like this. I have some clients were
we have to send out their laptop about once a year, because of the excessive
handling. Each time the display panel is folded up and down, there are
stresses on the panel, the ribbon cable, the connectors, and the hinges on
the case.

It isn't the cable below the display connector, because moving the hinge
has no effect, and squeezing without moving the hinge always has an
effect. It might be the cable where it terminates in the connector, but
I'm dubious because I couldn't make it fail and because that isn't a
stress point (cable taped down, no forces to break it).

I'm still guessing it's a contact failure within the display
electronics, where contacts were pressed together but (deliberately)
never soldered. If it gets really bad I'll open it up again and try
again, replacing if unsuccessful; until then I'll live with it.


Thanks,
Dan

--
Daniel T. Griscom Work: (781) 665-0053
Suitable Systems Fax: (781) 665-7106
152 Cochrane Street
Melrose, MA 02176-1433 http://www.suitable.com/