A single horizontal line across the screen indicates a failure in the vertical circuit, often requiring replacement of the LA78040 IC and checking the 24V supply from the flyback.

Typically uses the LA78040 or STV9302 IC.

Sharp TVs are famous for their protection circuits. Common triggers include: Faulty vertical IC. Dried-out capacitors in the B+ (115V–125V) line. Defective Horizontal Output Transistor . Service Mode Access

Often the TT2140 or MD1803DFX .