Broken Tv Ir input

[imaginieus]

I cannot get the ir input on the tv to work. The tv was used and did not come with a remote. I tried a universal remote, the original remote, a new ir assy board, and nothing seems to work.

Does anyone know what could be wrong with it?

[jts1957]

Missing a power source, bad solder joint(s), cracked P.C. board trace(s), open resistor (or other part), shorted capacitor (or other part) or bad IC in system control area. Remote function turned to "off" in a secondary menu (Hospitality TV's for example). Think that should cover most remaining possibilities.
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[torbjorn]

Another possibility is a faulty crystal or resonator for the tv's microcontroller. If its clock oscillator runs far off from the correct frequency, the software cannot decode the data from the IR receiver.

Check with a scope or a frequency counter with a low capacitance probe that you get a clean oscillation at about the correct frequency on both terminals of the crystal.