Take a look at our
ThinkPads.com HOME PAGE
For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message

X32 Screen - Flashes once but then dims completely

X20/X21, X30/X31, X40/X41 Series
Post Reply
Message
Author
honnoric
Posts: 2
Joined: Wed Jan 18, 2012 12:45 pm

X32 Screen - Flashes once but then dims completely

#1 Post by honnoric » Thu Jan 26, 2012 12:41 pm

Hi there,
I am having a problem with my (formerly) trusty X32 display, and having been through the forum still cannot shed light on the problem.
All is OK on an external Monitor.
On start-up the screen flashes up at full intensity for about a second, dims to about half intensity for another second then dims completely. The image is still just about visible, so it looks to be the CCFL backlight that is not staying powered up.

The fact that the screen is at full intensity initially (even though momentarily) suggests to me that the backlight is physically OK.

I have replaced the inverter (makes no difference) and checked all the connections that I can get to (have had the LCD panel out to do this) - and still the same problem.
I did notice when changing the inverter that the screen would occasionally flash to full intensity when the inverter was moved about, but it would never stay on.

I now see that the micro-switch that is operated by the lid close switch has come off the board completely - and so I am wondering if that is somehow critical to the power circuit (I can live without the lid dimming the screen when closed).

Any ideas of what to check next gratefully received

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 23812
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire

Re: X32 Screen - Flashes once but then dims completely

#2 Post by RealBlackStuff » Thu Jan 26, 2012 5:28 pm

That switch is Normally Closed (the little pin is in UP position), meaning it lets current pass through the switch.
If you press on the little pin the CCFL goes out.
Same thing if you remove the switch, the CCFL goes out.
Check where the switch was, and solder a tiny jumper wire across the old switch contacts.
When done, put some Kapton tape over it. If you don't have that, electrician's tape will do also.
Problem solved.
Lovely day for a Guinness! (The Real Black Stuff)
Lenovo: X240, X250, T440p, T480, M900 Tiny.

PS: the old Boardroom website is still available on the Wayback Machine
.

honnoric
Posts: 2
Joined: Wed Jan 18, 2012 12:45 pm

Re: X32 Screen - Flashes once but then dims completely

#3 Post by honnoric » Thu Jan 26, 2012 5:39 pm

Thanks for the info and have had a crack at it. But with no great success

There are three contacts underneath where the switch was seated. (Two on one side of the hole it sits in and one the other).

While testing to make sure I was connecting the right contacts (by holding the jumper across the contacts) the best I could get was for the screen to flash on again - I could not get the screen to stay lit up for more than a second.
So I do not know which contacts to connect, and am not convinced it will work.


I haven't got as far as taking out the board and checking if all is OK underneath - is this the next step ?

Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “ThinkPad X20/X30/X40 Series incl. Tablets”

Who is online

Users browsing this forum: No registered users and 43 guests