Check whether all the cooling fans on its upper side [back] are working or not. If not, check out the reason. If you wish to get some details, check the site linked here. http://electronicshelponline.blogspot.com/ Pull up older posts. Check the site in 'Mosaic' view. It will make search easy.
Disconnect the base of horizontal drive transistor, and now check it collector voltage. If it is found OK; [almost equal to its iput voltage]; check the voltage that comes to its base, from the IC pin. It should be below 0.1 to 0.25V. If found higher than this, the IC is faulty. If you wish to get some details, check the site linked here. http://electronicshelponline.blogspot.com/ Pull up older posts.
