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I have a working 600x with the only issue being the display. Works fine if I connect external monitor, so I assume video chip on motherboard is OK. Gotta be either LCD display or the ribbon connector. Is it worth fixing it? Where would I find replacement display? Any suggestions? Kind of a shame to throw it away since it still works. Or maybe someone here on the forum willing to sell theirs for spare parts?

Welcome to thinkpads.com!

Could also be an issue with the lid switch or a bad inverter board. If the switch is stuck in the "down" position, then that would cut off power to the inverter board. The inverter provides the necessary power for the backlight (aka, CCFL) to light up. If you shine a bright light downward from the top edge of the lid, do you see a faint image of the display? If so, that would indicate that the CCFL is not lighting up. Total lack of any image on the display could mean you have a problem with the ribbon cable and/or panel itself (make sure that you have pushed Fn+F7 a couple of times to enable the video display on the LCD).

Parts can be either obtained from here in the Marketplace forum or eBay.

Thanks for reply! Actually, I have been registered here awhile ago but lost my login

I just fired up 600X since I haven't used it in awhile, and can confirm that when I open the lid horizontally (fully flat), I can vaguely see what's on the screen at 180 angle lol!!! At the usual viewing angle its just a bright grayish light, while at that extreme angle I can make out icons on the desktop (running Win98) and there is a wide (1"-2") darker line across the screen behind which I can't see the desktop. Aside from this awkward viewing angle, this reminds me of when one of my older desktops had video card going south. Hmm, I know for sure that I can see display normally while external monitor is connected. Also, thinking out loud, since I'm able vaguely to see something on the screen at 180 angle - ribbon connection should be intact. Since the monitor is not black and some luminance coming through, inverter board you mentioned below should be providing some power. So, its gotta be LCD screen?

No, I'd say that the LCD screen is probably okay and that the inverter, whatever should be providing power to it, or the backlight is defective. Any one of those things going bad will cause no light from behind the LCD panel. You should be able to see a dim image on the screen at extreme angles or by shining a bright light upon it if there's none coming from the CCFL.

The chain of connections to inspect/re-seat would be the following:

- Sub card; plugs into a socket on the motherboard
- Lid switch, mounted on the Sub card
- Ribbon cable which plugs into the Sub card and goes to the inverter board
- Connector on the right end of the inverter card which goes to the backlight

Ray,

Really appreciate your guidance on this!!! I will let you know in reply as soon as I get a chance to take it apart and play around with connections.

Thanks!!!

Ray,

I just took 600x apart (too many screws lol!!!), and looked in the areas you suggested. Still the same problem, I can only see the display at extreme angle. Tested the switch on the left, and it turns monitor off while I press it down. So its gotta be inverter or backlight? Anything I can check in more details, perhaps measure voltage with multi-meter if I can get to any connector vias? Or should I just replace one thing at a time? Where can I get replacement parts? Not sure if from your signature you suggest to have spare parts?

For your reference, I took a few snapshots of the laptop inside.

http://i42.photobucket.com/albums/e328/ ... 600x-1.jpg
http://i42.photobucket.com/albums/e328/ ... 600x-2.jpg
http://i42.photobucket.com/albums/e328/ ... 600x-3.jpg
http://i42.photobucket.com/albums/e328/ ... 600x-4.jpg

Thanks!!!

Admin edit: Changed largish inline images to links. Please keep images to ~50KB and also edit the original post in the thread with "PIC" in the subject line. Some people are still on dialup or browse the forum with PDAs or cell phones.

Using one of your pictures, I've added notes on the items to check:

http://www.kawakami-ca.com/ibm_600x/ima ... onents.jpg

If you haven't done so already, re-seat all of the following: the Sub card, the ribbon cable that plugs into the Sub card and the inverter. If none of those things were loose, then leave the LCD bezel off and get something like this:

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0335360083 (600X backlight - 10L1350 $6)

Ordered replacement inverter board and just replaced it. But results are the same, the screen is bright white, and I can only view it at extreme horizontal angle. Any other suggestions? Thanks!

I'm sorry, but I may have mislead you about the inverter. I just went back and re-read your post from 7/4 ("At the usual viewing angle its just a bright grayish light....") after now seeing your comment about the screen being bright white. If there is any light coming from behind the panel then the inverter and CCFL should be okay. This can be best seen by turning the brightness slider all of the way "up" and viewing the laptop's screen in a dark room. If there is "bleeding" (a whitish glow) from around the edges of the display, then the CCFL is working and by default, the inverter is too.

If your video problem appears to be a "washed out" display, like a lack of contrast, then that's another problem. If, when you boot the system, does the IBM splash screen and associated white text on black background look normal?

you owe me $5 just kidding

Nothing looks normal at straight viewing angle. Head on it’s this whitish/grayish light which I can dim with contrast slider. But I can only see the splash screen, text, Windows, etc. when flip lid/display horizontally and view at this awkward 180deg angle. I guess you can call it "washed out" display when you look at it straight on. Is there anything I can do to fix it? I really want to get this laptop to work. It would be nice to have it along side of my currently working T42, T60, and new T400s addition.

Thanks!

rkawakami wrote:I'm sorry, but I may have mislead you about the inverter. I just went back and re-read your post from 7/4 ("At the usual viewing angle its just a bright grayish light....") after now seeing your comment about the screen being bright white. If there is any light coming from behind the panel then the inverter and CCFL should be okay. This can be best seen by turning the brightness slider all of the way "up" and viewing the laptop's screen in a dark room. If there is "bleeding" (a whitish glow) from around the edges of the display, then the CCFL is working and by default, the inverter is too.

If your video problem appears to be a "washed out" display, like a lack of contrast, then that's another problem. If, when you boot the system, does the IBM splash screen and associated white text on black background look normal?

With that (closely read ) description, then you might be having a problem with the ribbon cable, motherboard or LCD panel. At this point, I'd re-seat the ribbon cable connector (the one visible in your ThPd-600x-4.jpg photo) to the motherboard and also the one located at the back of the LCD panel. When you have the panel dropped out of the lid assembly, give a good look at the ribbon cable along its entire length and see if there's any cracks or tears.