To diagnose whether a Sony TV’s 6‑blink error comes from the power / G‑board or from faulty LED strips, you use a mix of observation, basic voltage checks, and selective‑disconnection tests. The goal is to see if the problem is upstream (power‑board supplying bad voltage) or downstream (LED strips pulling abnormal current).
Step 1: Observe the initial backlight behavior
-
If the screen briefly shows picture or a faint backlight before cutting out and the 6‑blink code appears, that strongly suggests defective LED strips (voltage is present, but the strips fail and trip the protection).
-
If there is no visible backlight at all and the TV shuts down immediately into 6 blinks, the fault is more likely in the power/G‑board backlight‑driver section or the feedback/signal line (no correct voltage or no “on” signal to the strips).
Step 2: Power‑on while watching the panel from the side
-
With the TV standing upright, power it on and watch the screen edges in a dark room immediately on startup.
-
If you see one or two thin strips of light at the top or bottom edge lighting briefly and then dying, this is classic LED strip failure (often a short or open circuit in part of the strip).
-
If you see no backlight glow whatsoever, suspect the power‑board backlight driver or the “backlight‑on” signal path.
Step 3: Disconnect the LED strips from the power‑board
-
Open the TV, remove the back panel, and locate the LED‑strip connectors attached to the G‑board or backlight‑driver section.
-
Carefully unplug all LED‑strip connectors from the power‑board so the boards are still powered but the strips are disconnected.
-
Power the TV on again and watch the status LED.
-
If the 6‑blink error stops or the TV stays on (no blinking), the LED strips were causing the fault (shorted or leaking current).
-
If the 6‑blink pattern returns unchanged, the problem is likely in the power/G‑board’s backlight circuit (e.g., ICs, MOSFETs, capacitors) or the backlight‑error signal line.
-
Step 4: Test the LED strips with an external tester (if you have one)
-
You can connect the LED strips to a dedicated LED‑backlight tester or lab‑style power supply in current‑limit mode and check if they light evenly or show dark gaps.
-
If the strips fail to illuminate or only part of them lights up, they are defective and need replacement.
-
If the strips light normally when tested externally, but the TV still trips 6 blinks when re‑connected, the issue shifts back to the power‑board or signal path.
Step 5: Check key voltages on the power/G‑board
-
Use a multimeter to check the LED‑voltage test points on the G‑board (often labeled “LED+”, “LED‑”, or “BL‑ON”) while the TV is on (briefly before it trips).
-
If the LED voltage is missing, unstable, or far above/below the spec (often 80–150 V range depending on size), the power/G‑board is the root cause.
-
If the LED voltage is present and stable, but the strips still invoke the 6‑blink error when re‑connected, the LED‑strip side is likely faulty (internal shorts or leakage).
-
Step 6: Isolate the backlight‑error signal line
-
On many Sony boards, a single wire or pin from the backlight‑section acts as the “backlight error” feedback; if that line is shorted or floating, it forces the 6‑blink code.
-
Disconnect or insulate only that backlight‑error wire (often the 4th pin on a 14‑pin connector), then power the TV.
-
If the TV boots normally after isolating this line, the power‑board or the error line is at fault, not the strips themselves.
-
When to stop and hand over to a pro
If you are not comfortable measuring high‑voltage LED rails, desoldering, or swapping boards, stop at the disconnect‑LED‑strips test and treat the result as follows:
-
6 blinks disappear when strips are unplugged → LED strips are bad (replace them).
-
6 blinks stay even without strips → power/G‑board or error‑line problem (best handled by a technician).
This method lets you cleanly separate a power‑board fault from a LED‑strip fault and decide whether the job is DIY‑friendly or needs a pro‑level repair.