Facing TV Problems? Ask a TV Technician.
Hello, What is the model number off of the back of the TV?
Also, ATT can't check the connection between the box and the TV from their end. No Signal either means the TV's Mainboard has failed (which is not likely but possible), or that the HDMI cable between the ATT box and the TV is faulty (most likely). Has ATT run you through a reboot of their box, and also had you swap out that HDMI cable yet? These are the two most common causes of No Signal on the TV, which is why I ask.
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