Have the wall power unit checked. Next up is the LAPTOP POWER JACK REPAIR (google that) and after that it is usually the motherboard.
Bob
Hello, I have a Lenovo SL400 with a product ID of 27434AU. This morning, I went to turn it on but it would not power up. The indicator light that are normally working when the laptop is off were not lit. When I press the power button, nothing happens, no lights, no sounds, no movements. I attempted what was suggested here: http://forums.cnet.com/5208-7587_102-0.html?threadID=327647 but it didn't work. Thanks for your time.

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