Ps4 no signal

My ps4 is being detected in my tv because every time I plug my homi cable it it says playstation 4 game console. But it says no signal even though it's on. It has a white light on. I’ve tried the resolution thing but when I try putting it in safe mode still nothing appears. I’ve tried 4 hdmi cables. This ps4 worked before I unplugged it for about 2 months.