Notebook lcd screen flickers and goes white

Question

i have a toshiba portege 7010ct laptop. at times the display flickers and

/or goes white. i restore by changing the display mode, i.e, pressing fn +f5 to cycle from lcd to lcd/crt to crt only and back. at times the display is stable at other times it goes on the blink again. i have reseated the lcd connector but this problem is not there all the time but crops up occasionally.