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The charge indicator LED is solid white when connected to the power adapter, so I know the battery is fully charged. A few days ago, I put my laptop into hibernation. It seemed to shut down nicely. Later that day, I pressed the power button to turn it on, but nothing happened.The next day, I opened it up and found the power button had broken from the power button board. So, I purchased a new power button board, part 774599-001 and installed it. Still, when I press the power button, nothing happens. No lights, no sounds, no clicks – nothing.So, I may have one of these three conditions:1. Something on the system board has failed. When it didn’t power up, I may have pressed the power button with too much force and that is what broke the button. Now I have a new power button board, but the m/b is still faulty.2. The power button board that I installed is faulty. I can get a replacement for the replacement.3. I somehow caused a new issue while I was working on it.I have tried powering up with and without the power adapter, performing a power drain, starting without the battery connected, and holding the Windows-B keys. Nothing has helped.What should I try next?Does anybody know which of the 6 pins in the power board cable can be shorted together to start the computer? If that works, I will know that the power button board is bad, and the system board is good.Where can I find a schematic for my system board?
Hi @wiley1 , Here’s a link to the schematics (I hope relevant to your motherboard) Here’s an image of the connector CN3 which shows the pinout of the power button board that may help (pins 2 & 6 for the power button). Check for voltage on +3V_RTC if temporarily shorting these two pins out doesn’t work. The LID switch is used for the screen backlight power control (on/off when lid open/closed). It is also used for powering the PC off when the lid is closed dependent on the power option settings in the OS e.g. sleep etc but not if the OS is not loaded
(click on image to enlarge) The maintenance and service guide for a 15 -u363cl model shows that the part number for the power button board is 774599-001. This guide is also applicable to a 15-u100cl so presumably it will be for yours also. Is there a HP part number shown anywhere on the original power button board to confirm what it is? What is the product number of the laptop as shown on the information label on the bottom of the laptop? I can’t find the service guide for your model using the HP support website above, and your model is also not listed here when searching for HP parts. I suggest that you look for the product number instead of the model number using the link just mentioned, to see if it shows up that way.
to turn on the laptop, with a paperclip, short a ground surface on the motherboard (top of a screwhole is good) and the bottom pin of the power board connector.
