How to inject a signal into a TV?

[old_tv_nut]

Those little (few pf ) caps don't get leaky, but could open (though not likely). More likely failures are the coils L10, L11, L12. Check L12 resistance to see if it is open. Should read 9.5 ohms, but if open, will read the 10k parallel resistor.

Edit: hope we are both reading the same schematic (rca_ctc16x_sams-0818-2.pdf).