For my G62 HP, I had that same problem and I fixed it by re-inserting the ON button's ribbon connection in it's holding plug, it had inadvertently come out. Look here at minute 3:12 where the pointer is, that's the one. You can't take the keyboard pad off unless you remove the screws inside the battery pack bay. easy job...though I recommend watching the video to figure out which three screws hold the keyboard in place. You do not have to take the whole laptop apart for that, although if you suspect the fan might need cleaning you might want to do the whole job.
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For my G62 HP, I had that same problem and I fixed it by re-inserting the ON button's ribbon connection in it's holding plug, it had inadvertently come out. Look here at minute 3:12 where the pointer is, that's the one. You can't take the keyboard pad off unless you remove the screws inside the battery pack bay. easy job...though I recommend watching the video to figure out which screws hold the keyboard in place. You do not have to take the whole laptop apart for that, although if you suspect the fan might need cleaning you might want to do the whole job.
For my G62 HP, I had that same problem and I fixed it by re-inserting the ON button's ribbon connection in it's holding plug, it had inadvertently come out. Look here at minute 3:12 where the pointer is, that's the one. You can't take the keyboard pad off unless you remove the screws inside the battery pack bay. easy job...though I recommend watching the video to figure out which three screws hold the keyboard in place. You do not have to take the whole laptop apart for that, although if you suspect the fan might need cleaning you might want to do the whole job.
https://www.youtube.com/watch?v=IFOXNhHPkgA