Lenovo Thinkpad T440p boots to black screen, and mouse pad does not fully work.

Discussion in 'SFF, Notebooks, Pre-Built/Barebones PCs' started by justinb386, Oct 5, 2014.

  1. justinb386

    justinb386 Member

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    I have this Lenovo Thinkpad T440p that I just purchased used today (for parts or repair).

    It boots to a completely black screen, but I can very faintly see the Windows screen if I point a flash light at it.

    Also, the mouse pad does not work, but the right and left clicker (on the built in mouse pad) work just fine.

    Does anyone here have any experience with repairing the Lenovo Thinkpad T440p?

    I am thinking that the LCD screen needs a new back light, but is there a back light part for the screen, or does the entire screen need to be replaced?

    I have a Lenovo Thinkpad T420 with almost an identical LCD screen, but the only difference that I could see is the pins (the T420 uses 30 pins, and the T440p uses 40 pins, if I remember correctly).

    Other then the amount of pins, the 2 screens look to be identical.

    Would I be able to use the back light from the T420 LED LCD screen on the T440p LED LCD screen, or are they different types of back lights?

    Also, what could possibly cause the mouse pad to not work (when the right and left click buttons work just fine)?

    Thank you very much for any help with these 2 issues.
     
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  3. kevinsbane

    kevinsbane Senior member

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    Try the trackpoint. Some users will disable the mouse pointer tracking on the touchpad if they are trackpoint users.

    Backlights ate also integrated with the LCD units nowadays, so you will have to replace the entire panel. Thankfully, LCD panels for t440p aren't that expensive. ($70-$100 depending on which resolution you get).
     
  4. brinstar117

    brinstar117 Senior member

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    If the backlight is out, but you can see a faint image on the screen it most likely means that the fuse(s) for the backlight are blown.

    I don't know the exact details for your particular model, but I know that yours has a LED backlight meaning that there is no inverter to replace. Instead the fuses are located on the motherboard and are very tiny. They are soldered on and require some delicate soldering work to replace.
     
  5. justinb386

    justinb386 Member

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    Thank you very much for the very helpful info. I really wish that I woyuld have seen your reply before I ordered a replacement screen, which after I installed, it did not help the issue. Still had the same issue after I replaced the screen. So, do you know how much most techs would charge to repair the fuse on the motherboard? Is the cost of the repair even worth it, or would I be better off just selling the laptop for parts / repair? Thanks for your help.