It will be difficult for you to fix it yourself - a TV doctor might be able to fix it for you.
It has a warm-up fault - very probably in the power supply - a component works for a while but as it begins to heat up it quickly fails.
Confidence - experience - test equipment and circuit diagrams will be needed. Else a can of freezer spray to selectively cool individual components.
You do not mention the make or model but no matter.
Good Luck...
April 2017
howtomendit.com for free repair help, information and advice.
