HP 15-R Laptop Power Button not working, or works when ribbon cable is unplugged

[Range16]

I encountered this problem on my HP 15-R137wm Touchsmart laptop, that I have seen others enquire about, and I think I might have the solution. At lease it worked for me: 

All of a sudden my laptop will not turn on. I push the power button, but nothing. Battery or AC power supply, it doesnt matter.

So I dissamble the laptop and I find that the power button is not working properly:

With the power button board (PBB) connected to the laptop it will not turn on when the button is pressed. 
When I unplug the PBB from the motherboard the laptop imediately turns on.
If I connect the PBB to the laptop while it is on, it will shut down, or go into sleep mode.

So I order a new power button board and cable assembly. It arrives, I install it, SAME PROBLEM!!!

So I play around with it a bit, I connect the old PBB to the motherboard while holding the PPB in my hand, and the laptop turns on!! Ureaka, I'm onto somthing.

Anyway, to make a long storry short, it appears to have to do with proper grounding of the PBB to the chassie of the laptop. There is metalic covered foam block adheared to the PBB that is suppose to ground to the laptop base when assembled. You need to clean that contact surface to insure good contact. That is all I had to do and now both PBBs are working properly. Hope this helps others!!

[iomare]

Hi,

Great job figuring it out and sharing.

All the best,

David