Lenovo IBM Laptop screen is blank

@avrickabel possibly a bad LCD or bad GPU. Connect an external monitor and if that works you will know that your LCD needs to be replaced. Now, word of caution. This series had two types of backlight. One being LED and the other CCFL. The CCFL version may have an inverter. Shine a flashlight at an angle against the screen with the computer on. If you can make out silhouettes of the screen etc.,then you know it is your backlight. You'd have to disassemble your computer and post some images of what you see with your question. That will allow us to help you further. Use this guide iFixitでの質問に画像を追加する方法 for that. This guide will help you with your repair Lenovo ThinkPad T500 Screen Replacement