Hi, my name is ***** ***** I have been in the home improvement and repair field for 20 years. I will be very glad to help you today. If you are not getting a signal from any of the HDMI ports the main board is needing replacement in the tv. If you choose to fix it yourself it is slightly difficult for someone who is quite handy. First would be an initial inspection of the internals of the tv. Looking for blown capacitors and physical damage and also looking for simple loose connections between the PCBs. (Printed Circuit Board). If there is no immediately obvious damage to any of the boards or capacitors then replace the main board. The main board is the board that all of the HDMI connection connect to. When searching for the correct board cross reference the model number of the television with the model numbers printed on the board. The model number alone will not always get you the proper board since it depends on what time of year the tv was made. You may also find the same board is used in several model televisions.
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