I recently ran into an issue with my Hitachi 55-inch LED TV where there were two thick horizontal lines visible across the entire screen.
As an experienced DIY technician, I set out to diagnose and repair the issue myself.
Troubleshooting the Issue
The first thing I did was power cycle the TV to see if the lines would disappear. Unfortunately, they persisted after turning the TV off and back on.
Next, I opened the TV’s back panel to visually inspect the internal components. Upon examination, everything looked normal with no loose connections or damaged circuit boards.
I then used my multimeter to test voltage levels on the power supply board and T-CON board.
The voltages were all within normal range, eliminating the power supply as the culprit.
Identifying the Faulty T-CON Board
Through a process of elimination, I narrowed the issue down to a malfunctioning T-CON (Timing Controller) board.
This small circuit board controls critical video processing functions.
After some additional troubleshooting, I confirmed the T-CON board was sending erroneous signals to the LED display, resulting in the horizontal lines.
Replacing the T-CON Board
With the source of the issue pinpointed, the only remaining solution was replacing the T-CON board.
I located a replacement online that was an exact match for my TV’s board.
Installing the new T-CON board was straightforward, involving disconnecting all connectors, swapping the boards, and reconnecting all cables.
After reassembling the TV, I powered it on and the lines were gone!
The replacement board functioned flawlessly, restoring the picture to perfect condition.
Replacing the T-CON board ended up being an inexpensive and relatively easy fix to resolve the horizontal line issue.
Through methodical troubleshooting and replacement of the faulty component, I was able to get my Hitachi TV working again without needing to buy a new one.
