CT-25G7 Dark Picture
 

My dad has a Panasonic CT-25G7F which is very dark even when all of the
onscreen settings are cranked all the way up. Is there a simple internal
adjustment or component replacement that may fix this?

thanks
Adam

CT-25G7 Dark Picture
 

A common failure on those is a high value resistor that goes between
the regulated 120V line and the ABL line off the flyback.

It is also possible that the tv has had excessive use and the picture
tube is simply worn out, but the on screen text would probably be
showing color bleeding and also not very bright.

No, do not try and adjust out a fault, it will simply make it more
expensive for a real technician to repair the tv set.