Panasonic TC-L42D2 Technical Manual page 42

Troubleshooting TCON Problems
LCD Panel defect
At times, symptoms of a defective panel may be mistakenly identified as a TCON failure. Beside a
broken LCD glass, most panel symptom would appear in a particular section of the screen. The
TCON provides pixel data to groups of row and column drive ICs located on the upper and side
edges of the panel. It is improbable that several of these ICs would fail at the same time. Therefore
many columns or rows of pixels that are on or off point to a defective TCON. A single row of On or Off
pixels cannot be attributed to the TCON. The TCON simply cannot cut out a single line of information.
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