There are basically three problems that would cause this, the Power Supply, the T-Con board, or the LCD panel itself has failed. 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 $150 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 $150 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 $600) 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.
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