Mitsubishi Ws-65813

This TV just shuts off on it's own at anytime. The green light stays on, but the picture just goes blue. a message on the screen says "check connections or power. The connections for RGBHV or YPrPb may be invalid". By turning the TV off and back on again, a picture returns, but then in a few minutes it goes off again, and the cycle repeats.
Any suggestions?