Still more questions about a possible LCD upgrade of the Thinkpad 600

[sergione78]

Dear friends of the Forum,
I'm aware that this question has been asked before, including for other TP models, but still wanted to share my experience.
A long time ago I recovered a 600 with a perfectly functional 12.1" screen, which unfortunately suffered a bad fate after a few months, having fallen from a height of one meter. Now, a few weeks ago I found an ad on ebay and took a thinkpad 600 not working, but with intact screen, except to discover that it was a 13.3".
To my disappointment, I only discovered at the time that the screens have different connections, even though the working plate contains the solder pads for the XGA panel connector and components.
Having failed to repair the damage to the motherboard (for the rest perfectly identical to the previous one except for some details) I thought it was a simple problem of soldering and I armed myself with a soldering iron and a hot air station (and a microscope).
I discovered that in addition to the connector, there are also other smd components to swap (capacitors and a couple of chips).
After having soldered all the components on the other plate and eliminated any shorts, at least the ones I managed to find, I turned on the PC and the backlighting turns on, but nothing is visible on the screen (except something when turning on personally it looks like an attempt by the graphics card to change the screen resolution).
Now, I ask you who have more experience than me:
1) are there diagrams for the motherboard and/or for the LCD panels in question? (found nothing all over the web other than service manual).
2) has anyone tried to do the same crazy thing as me before?
3) by chance, as far as you know, given that the connections are fine (it seems so to me but I could also be wrong) could it be a different matter? For example different firmware or bios settings?
Probably the matter can be easily resolved by buying another card, but I would like to point out that these laptop models are also becoming increasingly rare and consequently the prices for spares are increasing.
Furthermore, with all the non-working specimens out there, it's worth it in my humble opinion to investigate the possibility of being able to exploit all the hardware that can be found. Finally, it must be considered that the 13.3-inch TFT represents a big step forward compared to the smaller screen, even if I had used it at the time and it didn't seem as bad as many say.
Thanks to anyone who can give me information on this.

[solidpro]

I might be being dumb, but when you got a good 13.1" "lid" could you have not swapped the whole thing, including the LCD bezel and the ribbon connector over to the original one with the smaller screen?

It's possible if your original plastic lid was in better condition, that might have been able to be kept, but switching everything else.

I would have stopped at reverse engineering everything so as to only swap the LCD itself... as, unless I'm mistaken, you have tried to do.

[solidpro]

Oh, I just sold a bunch of 600 spares in the markplace for not much money, which included lids and inverters. I might have a spare LCD of some size, if you want me to check...

[sergione78]

thank you for your kind reply. Actually, if I have understood correctly (I'm not exactly a native speaker) what you suggest is exactly what I have already done. Obviously I changed the whole "lid", but the problem arises on the mainboard, which required many micro-weldings.
I wanted to understand if wiring diagrams of these boards does exist somewhere in the world.
In my humble opinion there are two possibilities:
1) I didn't pay enough attention to some component that was ought to be swapped;
2) The components are all and well soldered and the problem is firmware/bios (for example, the bios foresees an LCD panel rather than another) which perhaps I could solve with some other soldering, but it would be nice to know beforehand.
By the way, I'm not a techie. As for spare parts, I live in Italy, and a shipment to my country would cost many times the value of the spare part you could send me, leaving out VAT and import duties. sigh!

[solidpro]

Hi

I don't know enough about the differences between the 12" lid and the 13" lid but are you saying the ribbon cables were different?

I don't understand why you needed to improvise modifications to the mainboard because almost always, from the ribbon onwards, lids and screens are interchangable on the same model thinkpad.

1) Does the connector on the 13" lid match the connector on the 12" lid?
2) What does it connect to on the motherboard?

Photos?

[RealBlackStuff]

Guys, RTFM!
According to the 600 HMM there are THREE screen options: 12.1", 13.0" and 13.3", all with different cables, hinges, etc.
And all 3 sizes also have different motherboards!

[sergione78]

I see the matter has been misunderstood. As specified in my first post, I have two complete TP600 2645s, one of which recently purchased "to be tested" to be used for spare parts. The the other motherboard is perfectly functional (the one with the broken screen, so to speak).
When the parcel has arrived in my hands I realized that the TP I just purchased had a 13.3" screen. Once opened, I immediately noticed a different LCD connector so I tried to do some troubleshooting. The board had a fault somewhere so didn't boot.
SO I'm trying to see if I can swap parts between the two TP in order to make at least one functional.
I've certainly read the manual, and I've to say that it's perfectly useless, as it doesn't contain any kind of useful information, except LCD assembly are "FRU". It does not contain pinouts or wiring diagrams useful to a tecnician.
As for the motherboards, I've to point out that they are perfectly identical, except of course for the different video connectors, some smd capacitors (i suppose for CCFL and indeed it works), and the Texas Instruments SN75LVDS84, which according to the technical characteristics is a "flatlink transmitter".
which according to what I learn by reading the technical characteristics converts the video signals to be directed to the LCD panel.
Clearly, if the first card hadn't been set up for that I wouldn't even have attempted this exchange, but having everything I need, I'm trying anyway. I just wanted to know if here on the forum someone more expert than me has by chance the schematics of the motherboard (in its variants) or if someone has already tried to do something like this in the past.
Here is the pictures:




if you can't see the images i will upload from another source

[RealBlackStuff]

Can't see any pictures.
Try linking to e.g. https://imgur.com/

[sergione78]

Here are the pictures:


https://imgur.com/gallery/tlYOpJu

https://imgur.com/gallery/JKtp7VA

https://imgur.com/gallery/0JbhveI

[sergione78]

https://imgur.com/gallery/K2SkCRL

and after swapping components

[sergione78]

someone pointed out to me that the welds were not performed very well. Yes, I know, in fact I will check as soon as possible if the welds make contact and there are no shorts. I found the SN75LVDS84 manual and the connector pinout on the net, but without the wiring diagram everything is very difficult. Thanks to whoever wants to help me

[RealBlackStuff]

The only thing I could find: https://www.eserviceinfo.com/downloadsm ... anual.html
Scroll down and click on >> Download document <<
In there, see if section Video Subsystem helps.

If interested in 600 batteries, go to http://milnoc.com/OldSite/ and on the left, click on IBM ThinkPad Batteries

Whomever has any 600 schematics has been a master in keeping them from public view.
Nowhere to be found.

[solidpro]

600s are pretty common as muck in a variety of conditions, so I would sit on it and wait for ebay to come up with a replacement.

[sergione78]

From a logical point of view I cannot say that you are wrong, there are many difficulties to be faced and simply swapping motherboards would be easier. However, I personally think it is worth trying, maybe it will be useful to someone else. In any case, apart from the hardware, I found some info in the link document, the BIOS keeps track of the installed screen and the various combinations of resolution and refresh rate. Even the use of a monochrome LCD would also be foreseen??? Anyway, I have to study it better. I will keep you updated in the coming days.

[sergione78]

good evening dear forum members!
After a long time I remembered that I had asked for help with the screen swap issue on my TP600.
Well, I have to tell you that it was PERFECTLY POSSIBLE!
That said, it is not an operation that I would recommend, but for me the important thing was to succeed in the undertaking, considered by many to be impossible.
Greetings