NUC power button acting up?

[sudiki]

Have a NUC6i5SYH that intel won't support any longer as they discontinued it.  Sometimes after I run my anti virus and the system then shuts down, when I go to restart it again the power button won't work no matter how I press or "jiggle" it.  I found by accident that if I unplug the power cord at the NUC then plug it right back in; the power button will work every time!  When I plug the power back into the NUC the system "beeps"  (through the speakers I have installed).  This is an intermittent problem as sometimes the power button works but is seems to be getting worse and I have to do the power unplug/replug to get the button to work and the NUC to power up.

I at first thought it was the power button but I would think that it would be either good or bad and why does the power disconnect trick work every time then?

Any ideas?

[LeonWaksman]

1. In my first NUC - NUC6i5SYH, I got similar problem. When I've applied more force on the Power Button, the NUC started. So, my conclusion was that there is a problem in switch contacts. The switch contacts were oxidized. After removing the board, using Compressed Air Duster, I've cleaned dust from the Thermal Solution.
2. In this link, you may find explanation (an example), how to remove board from NUC housing (this is very similar NUC to yours). Not all explanation in tis clip is relevant for you. You may start  at 5:20. Since the WiFi card in your NUC is removable, I suggest that after removing the SSD, using a flat plier, unscrew the SSD standoff and remove the WiFi adapter from its M.2 slot. This is more safe than disconnecting the antennas cable.
3. Next, I've sprayed dissent amount of Servisol Super 10 Switch Contact Cleaning Lubricant, targeting the switch plunger. Since the switch is not hermetically closed, certain quantity of the cleaning solution, penetrated to the switch contacts. Naturally some solution also wetted the board and components near the switch.
4. You should wait some time (about 15 minutes), till the contacts are cleaned after applying the cleaning solution. So, be patient.
5. You may also want to use Power Switch pins 6-8, on Front Panel Header. Momentary short between those pins shall replace the Power Button. Please refer to paragraphs 2.2.4.3 and 2.2.4.3.4 in Technical Product Specification 

Leon

[sudiki]

Thank you but that doesn't seem to be my problem although when I put in a new M.2 board soon,  I'll look at doing that (cleaning the switch). 

It doesn't matter how hard I press or 'jiggle" the power switch;   it won't power on.  It only powers on if I disconnect the power cord from the NUC (at the NUC)  and then reconnect.  Then the power on switch works!  Every time!   Without pressing hard or "jiggling" the switch.

And when I plug the cord back in,  the system gives a short "beep" through the speakers which it shouldn't as it isn't on yet.....

Today it powered on with just a light press of the power switch.   Didn't have to do the disconnect power cord trick.

[LeonWaksman]

When and if you will remove the board, you may also disconnect the CMOS battery connector (located on board upper side) and reconnect it after 15 minutes.  This action will reset the CMOS.

Leon

[sudiki]

That's a great idea.  In fact, while I'm in there I'll just go ahead and replace it with a fresh one. The current one is about 5yrs old or so.

[n_scott_pearson]

That is a really worthwhile thing to do!

...S