600x - no screen display

[mnigro]

My 600x was still going strong until I recently booted up and had no screen display. Luckily I had an old monitor around that I plugged in. As I suspected, the 600x runs fine, but I have absolutely no display on the thinkpad screen, I can only use it with a monitor.

What are my options? Are there BIOS settings I can check that might bring the display back? Is it likely a mechinical issue, and if so, what needs to be checked/ replaced? Thanks.

[rkawakami]

A couple of troubleshooting procedures are as follows:

- try pressing the Fn+F7 key combination a couple of times. That will cycle the display between the LCD and external VGA port. I'm assuming that you have already done this as you say an external monitor works fine.
- flick the lid switch in front of the left hand side hinge. If it's broken (basically "down" all of the time) then the display will remain off no matter what you do.

If the screen lights up around the edges and you have control over the brightness slider but the screen remains "black":

- re-seat the LCD ribbon cable coming off in the area of the right hinge

If the screen doesn't light up, shine a bright light upon the LCD (at an angle usually works best) and if you can see a "ghost" image of the video signal:

- re-seat the LCD ribbon cable coming off in the area of the left hinge
- re-seat the Sub Card, what the left hand side LCD ribbon cable plugs into
- re-seat the inverter card behind the bezel of the display, at the bottom or replace it with one that is known to work

If you do see some pixel activity on the display but it remains dark and you've tried the solutions above, then most likely the backlight (aka, CCFL) inside the display has died. The only way of determining that is to replace the display with one that is known to work. It is also possible to swap out the CCFL. A member here, jamiphar, performs this service.

I'd say the two most common problems are the CCFL or the inverter card dying. You can generally find an inverter card for $10-$15, either here in the Marketplace or on eBay. The CCFL costs around $20 but can be hard to replace if you haven't done one before. In cases where the CCFL is determined to be defective, usually people replace the whole display or even the entire lid assembly (LCD, inverter and cable). Less common problems would be something on the motherboard went bad or the LCD ribbon cable cracked somewhere or the lid switch on the Sub Card broke. That Sub Card can also be found fairly cheap or the switch replaced.