Sony · TV error code

Red LED blinks 3xMain board / board communication fault

Single source High-voltage / caution

Unlock what this code means, its causes, tests and parts

Full library + AI assistant for $34.90, one time.

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

Related diagnostic guides

Guide · TV

TV won't turn on (standby light only, or blinking)

Separate power-delivery problems (outlet, surge strip, remote) from internal failures. A steady standby light with no response is often remote or button related; a blinking light after a clean power cycle on a good outlet is a hardware fault, usually the power supply board.

5 steps ~45 minmoderate

Guide · TV

Sound but no picture (backlight / LED strip test)

The flashlight test tells you in one minute whether the panel is producing an image with no backlight. If you can see a faint image, the LED strips or LED driver are the likely fault; if not, look at T-con or main board.

4 steps ~90 minadvanced

Component test · TV

T-con (timing control) board: board or panel?

The T-con converts video from the main board into the signals that drive the panel rows and columns. Loose ribbons, a blown T-con fuse or a failed T-con cause image faults; lines that stay fixed in the same place usually mean the panel itself.

5 steps ~45 minadvanced

More Sony tv codes

Sony · TV

Red LED blinks 2x

Power supply protection

Cross-checked High-voltage / caution

Sony · TV

Red LED blinks 4x

Backlight driver / power or main board

Single source High-voltage / caution

Sony · TV

Red LED blinks 5x

T-con / panel fault

Cross-checked High-voltage / caution

Sony · TV

Red LED blinks 6x

Backlight fault

Cross-checked High-voltage / caution

Sony · TV

Red LED blinks 7x

Over-temperature

Single source

Sony · TV

Red LED blinks 8x

Audio circuit fault

Single source High-voltage / caution