How long have you had the set for, and when did the problem occur?
Additionally, what is connected to the TV for devices (DVD, cable box, etc.), and do you have the same issue regardless of which INPUT you select?
If you press MENU, does the MENU come up OVER the line, or behind it?
Please disconnect the set from AC power, then press and hold the power button on the TV itself (not the remote), for 10 seconds. After another minute, plug the set back in and press power once. Do you still have the same problem?
There are basically three problems that would cause this, the Power Supply, the T-Con board, or the LCD panel itself are failing. Voltages need to be measured at the power supply outputs, using a DMM with nothing connected to it but AC Input. If the readings are proper, then the other boards need to be connected one at a time, until one causes the voltage to shut down at the output. Price to replace the power supply is around $100 parts and labor. If the supply outputs power with all of the boards connected, then the T-Con needs to be tested. The T-Con will run you around $60 to have replaced. If the T-Con tests good, then the LCD Panel has failed and will cost you more than a new TV (around $275) to have replaced and it is not cost effective to repair this set. I wish i had better news on this set, but the fact that the MENU does not come up clearly, indicates a failure in one of the components responsible for powering, and processing the LCD panel itself (including the LCD panel).
If you do not have experience testing live voltages on a circuit board level, then I would suggest using the link below to locate a tech in your area:
If you need further assistance, let me know.
You cannot test the T con without replacing it with another to see if it works.
The first thing you'd want to check is the caps on the power board for bulges or leaking. Any of these needs to be replaced.
Please only proceed if you have experience measuring live voltages on a circuit board level.
Next, use a DMM set to DC volts, find a common ground on the power supply and probe all of the Outputs for voltage (correct voltages will be stamped on the power supply at the outputs). Do this with NOTHING connected to the Power supply but AC power. If a voltage is missing/ fluctuating, then the power board needs to be replaced.
If the power supply outputs its rated voltages, then connect the other boards one at a time until one causes it's voltage to fluctuate or drop. This board would have the failure causing the problem and would need to be replaced.
A good source to locate replacement boards is http://www.shopjimmy.com/ and http://www.discountmerchant.com/