I'm having issues with my Lenovo T490. It turns on and the charging LED lights up when plugged in, but I'm not seeing the Lenovo splash screen. I've already tried swapping the RAM, removing it entirely, changing the SSD, and checking all the ribbon cables. Everything looks good on the board. When I power it on, the keyboard lights up for a moment, then goes dark, leaving just the power button lit. The screen itself works since I can trigger a test mode with Fn+Ctrl+Shift+Power, which shows colors on the screen. I suspect it might be a corrupted BIOS. Any suggestions on what else I could try?
1 Answer
Have you tried disconnecting both the CMOS/RTC battery and the main battery? Hold down the power button for about 30 seconds, and then try powering the laptop while it's plugged in with both batteries disconnected. Let me know if that changes anything!
I did that, but unfortunately, it didn't help much. The power button blinks a few times before going back to the same behavior. I found this video where the laptop shows the same issue as mine around the 8-minute mark, but it magically turns on after a few attempts! The guy was using a multimeter, but I can't figure out what he did.