T42 LCD Black could do with a little help

[deckchair]

Hi Guys
First post so be gentle. I've trawled the forum for hours and just need a little help as other posts don't seem to be quite the same as my symptoms

T42 type 2373
Been working fine for years and very impressed. But last night screen suddenly went black with no warning. Everything else works fine, I can log onto it on network and do remote desktop on it as usual and an external monitor works fine from it. All icons on screen base still work as normal

Note -unlike mentioned in other posts stating a black screen
there is NOTHING on the screen ie no faint windows operating in the background and there was no pink tint to the screen beforehand. There was nothing intermittent about it, just straight from working fine to total blackness. The screen lid close switch works fine and puts Thinkpad into standby as usual

So I'm thinking NOT inverter, NOT screen lamp as there's nothing on screen to illuminate

In the past I've changed hard drive, MB battery, fan, keyboard etc so I'm used to taking it apart but no experience with screens

Most grateful for any help

[Harryc]

Start be reseating the LCD cable on both ends. Requires completely dismantling the LCD to get at the connector behind it. If that's not it, then replace the LCD cable, check fuses on the systemboard, and replace the LCD, in that order. If that's not it then your looking at a system-board problem other than a fuse. As far as checking fuses, start with the fuses right around the LCD connector on the system-board. Look for a member called poshgeordie and follow the fuse chart in his sig. You can contact the same member for repair ideas in the UK if you're not up to this yourself.

http://nickpaton.fireflyinternet.co.uk/ ... 0links.pdf

[deckchair]

Thanks Harry
Latest Update
Whilst viewing and operating the Thinkpad through an external monitor this morning, pressing Fn/F7 brought the Thinkpad screen back on again and it all worked fine for 30mins and then, just as suddenly as before, black screen again. So I'm thinking that rules out inverter and lamp

So I'll be tooling up and checking the lcd ribbon connectors as you suggest unless that changes anything?

Super! Thanks for the link

[Harryc]

No change, basically the same procedure...but a fuse would not be intermittent, so forget about that.

[deckchair]

Lovely. Does seem to be heat related. Booting up now after 20mins rest the screen is fine, so yes, it can't be a fuse

Is there a thermal sensor safety shut down of screen if say the board cooling fan is ineffective? I can hear cpu fan going but it seems not to be blowing out as warm air as usual

[RealBlackStuff]

AFAIK no, there's only a sensor for CPU overheating.
When your LCD is black, try moving the lid back-and/or forward, see if the LCD comes on again. If so, LCD-cable = culprit.
Do NOT flex the base!

[deckchair]

Ok Will do. Screen is working fine at the moment. 20mins on

[deckchair]

Ok there it goes. Hit the 25min max
I was viewing on external monitor as well as Thinkpad screen and both went dead at the same moment. Moving the screen at the hinges had no effect. So is that ruling out lcd ribbon connectors now as the ext monitor went out too?

Is there a forum link to just what the "dreaded GPU" fault actually is? And is it likely to be the GPU?

I'm now getting start up fault bleeps "dash dot dot"
(Long time since I did morse code )

[Harryc]

One long and two short beeps, and a blank or unreadable LCD.

1. System board
2. LCD assembly
3. DIMM
http://www-307.ibm.com/pc/support/site. ... 46018.html

Try reseating the RAM.

[deckchair]

1. System board
2. LCD assembly
3. DIMM
Ha! All bases covered there then

Try reseating the RAM.
Ok, doing that now

[deckchair]

Ok Ram contacts cleaned and reseated
Normal start up- no bleeps- all normal, good looking screen so far

Timer started. Fingers crossed

Much appreciating your help guys

[deckchair]

10mins and blam. Both Thinkpad and ext monitor black screen

Ok Update
I logged onto it using remote desktop and there was a warning flag on screen (always handy when the screen has gone blank )

It says
ati2dvag graphics driver has stopped working- reboot your system etc

[poshgeordie]

I'm wondering about faulty RAM - I had a similar fault last week which was down to no-name RAM module

Regarding fuses - HarryC is referring to this document. The fuses relating to the LCD are F3, F7 & F8, however none are resettable so it's unlikely to be them (as said before).

Also the ATI graphics chip does have separate video outputs so it is possible to have the external working and internal not.

At this point I'd suggest disconnecting the internal screen and running only on external to positively rule out the screen.

Also if you have two memory modules fitted, remove on and try again, and then remove the other and try again. Also for completeness you'll need to swap them around the slots and repeat the test - again to positively rule out the memory modules and slots.

Also download PC Doctor. Run the .exe file to extract the .iso file. Use ISO Recorder to burnt it easily.
Run PC Doctor as a bootable CD ( press F12 on boot and select CD) and in particular concentrate on Memtest memory test, but it's worth doing a full test.

Just read your last result - 10 minutes and error message - a quick google indicates an overheating graphics card / chip - mmm I'm wondering if it is the graphics fault... Has anyone else got any ideas?

I'd be interested to have a look at it, and if that would help please either email me to nick@reflowrepairs.com, or a PM.

[deckchair]

the ATI graphics chip does have separate video outputs so it is possible to have the external working and internal not.
The external and internal graphics go dead together

I have only one memory module fitted

I'll try and do as much as I can on my own as it's so important for my work. It's either fast fix or get another one asap

Is there a separate graphics card? I can't remember now

[poshgeordie]

No there's just a graphics chip soldered to the motherboard. It's the ATI chip to the bottom right hand corner of the CPU.

Unfortunately I don't have a working board I could send you but I would turn the board around within the day if that helps.
Also I may have a working board tomorrow to at least lend you.

[deckchair]

Ok Thanks for that. I have to go to work now for a few hours (Groan) but I'll be investigating further later today

Many thanks again

[Harryc]

ati2dvag graphics driver has stopped working

Any time I've run across that error it turned out to be a loose GPU. YMMV.

[poshgeordie]

PM sent - could you telephone me?

[deckchair]

Good news! She lives again!

I stripped everything out down to the motherboard and cleaned everything and all contacts, particularly around GPU and she's been up and running now clean and cool for over 2 hours
Very many thanks to all contributors. The collection of information and knowledge helped me enormously and saved me a lot of time

Now i need to fix my boiler and washing machine

[deckchair]

Ah just when you think you're ready to put your feet up
Bam! blank screen again

I hadn't noticed it before but this thread is very related to my symptoms, even mentioning the ATI driver fault message

http://forum.thinkpads.com/viewtopic.php?f=2&t=33952

The ATI GPU is getting much too hot for my liking and cycles hot/cooler every 10secs or so and that doesn't seem right. It's too hot to hold on to and as my problem is heat/time of power on related it's all pointing to a loose GPU issue

Running PC doctor didn't find anything so I would think me being a little clumsy in picking it up has flexed the board and caused the GPU to lose electrical contacts

[rkawakami]

No change, basically the same procedure...but a fuse would not be intermittent, so forget about that.

Does seem to be heat related. Booting up now after 20mins rest the screen is fine, so yes, it can't be a fuse

There is such a thing as a resettable fuse.

ref: http://www.littelfuse.com/products/Rese ... 6L200.html
ref: http://www.iihr.uiowa.edu/~hml/people/k ... pptc01.pdf

edit: Took me a few minutes to track this down, but here's a picture of what's on a T23 motherboard near the LCD connector:

http://www.rkawakami.net/ibm_t2x/let.jpg (look just below the white connector, in the middle)

The green square with the "7 X (upside down) 7" is one of these:

http://www.tycoelectronics.com/catalog/ ... SMDC075F-2

[rookworm]

Good news! She lives again!

I stripped everything out down to the motherboard and cleaned everything and all contacts, particularly around GPU and she's been up and running now clean and cool for over 2 hours
Very many thanks to all contributors. The collection of information and knowledge helped me enormously and saved me a lot of time

Now i need to fix my boiler and washing machine

so... you think that the problem was due to gunk inside the machine ???

[poshgeordie]

Ah just when you think you're ready to put your feet up
Bam! blank screen again

The ATI GPU is getting much too hot for my liking and cycles hot/cooler every 10secs or so and that doesn't seem right. It's too hot to hold on to and as my problem is heat/time of power on related it's all pointing to a loose GPU issue

Running PC doctor didn't find anything so I would think me being a little clumsy in picking it up has flexed the board and caused the GPU to lose electrical contacts

Really sorry to hear that.

The graphics chip will run up to 65c + and will be too hot to touch, so it is normal.

I hate to say it but it sounds like a typical graphics fault....

I'd strongly suggest not doing anything with the chip (including pressing down on it etc) because as it stands it should reflow very easily and the less you 'do' with it the less damage is potentially done to it.

If I can help get in touch and I'll get something arranged for you.

[deckchair]

Ok Email in your inbox
Cheers
Brian

[poshgeordie]

And the reply in yours too Brian!