I have an LG TV model RP-21FA 39B this TV does not turn on, when I give power it turns on the standby LED only while I do not give it power the stamby does not turn on. I changed the regulator, the SE 110 the KIA 7805 the KIA 78RO9 PJ the IC 501 which is the LG 631 9R and the large capacitor of the main source and the problem persists, I want someone to help me solve this problem. Thank you.

The horizontal transistor is fine and I tried it I don't know what the problem is.