Screen won't come on when power key pressed

[Android Central Question]

When my S5 is locked & the screen is off, if I press the power button the screen may flash on for a fraction of a second and then go dark. The keys (back, etc.) at the bottom of the phone light up as normal but do nothing when pressed.

Pressing the power button a second time turns off the key lights. Pressing the power button the 3rd time is the same as the 1st time and the cycle repeats.

Sometimes (maybe 1 in 20 times), pressing the power key causes the display to come on and stay on and the phone is fully usable.

The phone has not been wet or sustained any physical shock.

Does anyone have any idea if this is a hardware or software issue or know how to fix it?

Many thanks for any help.

 

[Jobe77]

I also own a S5, and I'm sorry to inform you that the screens are REALLY bad, there have been many discussions on many forums.

Some screens flickers, some only got light on half of the screen, and mine flashes when I turn on/off the screen.

If you have warranty I suggest you return the phone.
if not, you could turn it in for service (but you got to pay for it your self..)