HP Elitebook 840 g4 keyboard blinking but will not turn on

[SDDS-Tech]

I have an EliteBook 840 G4 that was working perfectly an hour ago. I logged off and stepped away from the notebook. I tried to turn it back on but am unable to. The keyboard (all keys) blinks one long blink, no LEDs flash, no beeps, just the keyboard. I have removed the battery and tried to turn the notebook on with just the ac adapter with the same results. I tried holding the windows key and the b key down simultaneously and then the power button with and without the battery with the same failure. Any help would be greatly appreciated.

Thanks in advance!

[SAM11112]

It may be caused by insufficient power of the laptop, loose hardware or water in the laptop, and operating system problems.

[SDDS-Tech · Accepted solution]

Thanks for your response. After a slow and tedious afternoon I found the issue. The antenna leads for the wireless lan card were shorting out. Once the leads were in the proper location and insulated from the back case cover everything is back in good working order. Lesson learned check for the obvious first!