SONY TV BRAVIA XR X90K WON T TURN ON RED LIGHT BLINKING General Troubleshooting

Power Supply Board (G-Board)

The Power Supply Board is responsible for converting AC to the DC rails required for the logic board and the LED backlights. In FALD sets like the X90K, the PSU often fails under the high current demands of the XR Contrast Booster, leading to a shutdown and a red protection blink code. Replacing this board restores the necessary 12V and standby voltages.

Main Board (A-Board)

The Main Board manages the TV's boot sequence and diagnostic handshakes. If the processor or the eMMC storage fails to initialize, the system triggers a red blink code (often 2 or 3 blinks) to prevent further hardware damage. This is the secondary suspect if the Power Supply Board tests healthy.

Internal LED Backlight Strips

A failure in one or more zones of the Full Array Local Dimming (FALD) array will trigger a 6-blink red LED code. If the TV attempts to 'click' on before immediately blinking red, a shorted LED or open circuit in the backlight array is the likely mechanical cause.