phone aint turning on..

Thanks David, your solution worked for me. My phone (stock android, not rooted) wouldn't turn on until I did the following;

1. With no power connected, hold down the volume up and power buttons.
2. Continue to hold down both buttons for 60 seconds.
3. While still holding down the buttons, insert the micro USB power source.
4. On my phone, this caused the red led to illuminate (the first sign of any life on my phone for days)
5. Release the volume / power buttons.
6. The red led went out and the charging display was shown.
7. Wait a few minutes and switch on the phone

I think that I'd got the phone into some sort of hibernate mode, it had been on charge all night but after I finally managed to switch it on following David's advice, it was only showing 30% charge, about the same charge as when it originally failed.

James' answer was integral to solving the similar problem for me. Phone powered itself off and would not power back on. Tried all the Google troubleshooter steps to no avail. Talked to Google support and got no further. They transferred me to LG support to apparently learn about repair options. The LG staffer was a totally incompetent person who kept telling me to look things up in my settings on my phone.

Then I found helpful information on opening the phone on this site's tear down. I ordered a new battery and bought a Torx T5 driver. I took the back cover off, disconnected the battery, tested the power switch and finally removed the battery to prepare for replacement (the part had not yet arrived). Then I ran into this posting and with the battery disconnected, followed James' suggestions and the phone came to life. I then reconnected the battery and it charged and closed it up and it works great. I am left wondering if I could have followed James' steps without opening the phone and removing the battery and had the same result.

Thanks, James.