TVs

Vertical or horizontal lines on screen (T-con vs panel)

Decide if the lines are in the source, the T-con/ribbons, or the panel. Lines that pass through the TV's own menu are internal; single fixed thin lines usually point to the panel's COF/ribbon, grouped or shifting lines more often to the T-con.

Cross-checked ~60 min advancedBrands: All

Before you start

  • Do not press or shim the bezel to 'fix' lines; COF tabs are bonded to the glass and break easily.
  • Disconnect power before reseating ribbons; never handle panel ribbons live except for the trained-tech isolation test below.

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Vertical or horizontal lines on screen (T-con vs panel) · OnCall Tech