I own a Nikon D7200. Recently I changed Pv button to playback. Previously it was viewfinder grid. I needed the viewfinder grid so I left it on and then changed the button. When I switch off my camera, the grid is still on. Will it consume battery? Thanks in advance
The displayed grid per se draws almost zero power from your battery (imagine a dumb/classical digital (LCD) wristwatch with a small button cell battery lasting for 10+ years) - unless you use display illumination etc.
If the viewfinder backlit were on for all the time, this could mean quite serious battery discharge problem though.
One of my film cameras is a Nikon F80, and it has this same feature. Film cameras' batteries tend to last months to years (and aren't rechargeable), so if there is a significant power drain, it should noticeably affect the battery life.
My experience - it doesn't. Because I don't use this camera much, the batteries are now three years old (or so) but still work fine, despite the grid display. The power draw, if any, must be exceedingly low.