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 Device you're watching?
If you bring up the MENU on the TV itself (not the Cable Box remote), does the MENU also flash colors, or does it stay on the screen normally?
Thank you for the reply.
Unfortunately, this indicates a failure within the TV that requires service.
Do you know how to use a DVM, and are looking to repair this yourself?
Or are you looking for a diagnosis and repair estimate?
A DVM is a Digital Volt Meter and you would need to be comfortable meauring Live Voltages inside the TV. If you've never done this before, then I would not suggest trying it on your TV as your first try.
Can you please check the model number off of the back of the TV? The model number you posted is not valid.
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 $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 $100 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 $200) to have replaced and it is not cost effective to repair this set. I wish i had better news on this set, but the symptoms you're having indicate 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.
If not, please do not forget to rate my answer.