Blown fuse or not? If blown,check for shorted components at the power supply and in horizontal secti0n,if fuse n0t blown,check for any opened up component,check capacitors and resist0rs too. That simple! Dont get your mind in exhausti0n, another way and effective way if fuse n0t blown,check for an open or bad solder in the power supply and horiz0ntal secti0n,