my tv is a panasonic tx-w28r4dp . how can i fix the problem ?

the initial problem was intermittent whereby
after appprox after 30 minutes use the tv would go into standby mode, it would then engage for the same period after restarting, until recently where it crashes into the standby mode on permanent basis upon switch "on".i see from recent questions /answers that there is an indication that ic 451 is the most likely culprit which may create the fault. do you think there is a strong possibility that this is the problem on this occasion.
many thanks in anticipation of your reply
zorba