Thinkpads Forum

My brother's i1124's screen is acting up. One moment the screen back light is all working fine and dandy then the next all you'll see is but a shadow of images as if its working but just dark. I think it is the back light, but does it need replacing? I mean it works intermittently but could be just cables or connectors or should I really shop around for a new back light? Thanks.

Intermittent problems bite... could be any of 4 things...

backlight itself
inverter
cable from motherboard to inverter
cable from inverter to backlight

I would 1st check the connections,,, does it make any difference as to what angle the lid is open?

If the bulb lights, and the connections are good, I would 1st suspect the inverter board over the light itself.

Thanks for the reply. It does not matter what angle the screen is set at. Its just dark right now. It happened after turning it off from a prior session. The next time I turned it on, its all dark. Now that you mentioned it, if it were the cables, you wouldn't be able to see the darked out images of your xp session right? If you shine a flashlight you can see what screen you are at in XP. Is the inverter board regulating the back light too?

No, the cable for the LCD (think vga cable on a desktop monitor) is separate from the back light cable.

Motherboard/video card --> LCD
Motherboard --> inverter ---> back light

The reason i asked about angle is this is a sign of a bad connection/cable. So far the 2 laptops I had go dim on me have been the inverter, you said it works sometimes, this leads me to think inverter, usually when the lamp dies, it dies... inverters seem to get flaky before they die. At least that's how it's been for me.

P.S. hopefully it is just the inverter ($20 eBay), because good luck finding the lamp without buying a parts machine

Thanks. That really was helpful. You've help me narrow down the problem. Based on our analysis, it could be the inverter. When I took it apart, it has 2 connections: 1 ribbon cable coming of the back of the lcd then a jack that gets to be plugged in from the backlight. Since its getting flaky, that would explain why the backlight isn't working. Whew! I thought it was the back light. This machine's so rare I only found 2 people selling it 5 months ago and now they're gone. At least here where I live. Again, thanks for the brain power.

Keep in mind i didn't say the backlight is good, I would just suspect the inverter 1st if the connections are good based on your description of the issue, plus it is the cheaper and easier to find, so I would start there

Did you get any further results on this? Or did you find a source for spare parts for the i Series 1124? I have one of these too, but the display cable of my i1124 is damaged, it only works for a specific display opening angle, otherwise the screen is just white. I have been searching for a cable for a while now, but didn't find anything.

@ iYassin...Sorry, its been a while since I last visted the site. The thing was, I found a shop claiming that they could repair parts. And they're saying that after diagnosing the problem, it was the flex cable. But, reading your post in your own thread on this after googling about parts for the same model, I cannot match what is happening with your own wih my bro's. I mean, I can make out the images in the display. I can see the start button on XP, the current window I am working on etc. You just have to shine a light on the screen.

From the looks of this, it cannot be the flex cable coming off the board going to the screen. Your's whites out: Your backlight works, but there is no display of data. t looks definitly like your flex cable from the board is the culprit. Mine on the other hand, has images displayed, so that flex cable is working. Its just dark enough but still being able to see images on the screen, like shadows in evening twilight.

That was why I concluded in a much earlier post that it could be the back light lamp or the inverter that supplies power to the lamp. But these things are also hard to find. Its been what? 7 months and I still couldn't find a thing. These machines can run forever, but like tanks, without parts, its just a dead pile of metal. In this case, dead peices of electronics put together to look like a laptop... But I ain't givin up.. not just yet.