VU 24 inch led TV stand by not release step by step processor

this board use in VU company 24 inch led TV

.In this board have a problem is stand by not release 

  • processor how to identify the problem. if this kind of problem is come 
  • First step to check all required voltage for system ic 
  • Check 5v ,3.3v, 1.2v  and some time 1.8v also this voltage is required to turn on stand by 
  • I check this voltage show ok then my next step to write software in to the flash ic 
  • Then i write it. but problem has same then i check crystal frequency 24 MHz 
  • It show OK then my next step to replace system ic 
  • Then i replace system ic 
  • After replacing system ic my set turn on stand my 
  • It mean my step ic is faulty