There are 11 blink codes built into a Panasonic television, as of 2015, all of which relay the fault diagnostic circuit's detection of errors within the TV. The blink codes vary from two blinks up to 12 blinks, each indicating a different problem.
The blink system is designed to detect and relay information about any faulty circuitry happening within the TV. To activate the fault diagnostic circuit, press the ON switch located on the TV and watch it to carefully count the blinking lights. Two blinks occurring on a plasma Panasonic, for example, means there is a 15V SOS D_BOARD / P-BOARD error, or a problem with the P-Board that must be addressed. Three blinks indicates a 3.3V SOS D BOARD problem that has occurred on the D-Board. These errors occur within the TV but can often be fixed by experienced technicians without taking the device apart.
Additional codes include 11 blinks, indicating a problem with the fan, or 12 blinks, indicating a problem with the speaker. To ensure you have detected the correct error, switch the TV on and off multiple times and watch carefully for the number of blinks. The blink codes can vary slightly, depending on the Panasonic TV model.