How I Fixed the 2 Blink Error in Sony KDL-46HX750
The 2 blink error in Sony LED TVs usually indicates a power supply-related issue. In this article, I’ll share how I diagnosed and fixed the 2 blink protection error in the Sony KDL-46HX750 model, using a simple multimeter and solid fault-finding technique.
- Symptoms of the Fault
- Red LED blinks twice repeatedly when the TV is powered on
- No picture or backlight on the screen
- TV remains in protection mode
Understanding the Root Cause
Sony KDL-46HX750 has a separate power supply board that outputs 12V, 3.3V, and other voltages via buck converters on the mainboard.
- The 3.3V powers the system IC
- The system IC activates the main 12V rail and PFC circuit
- This 12V is distributed to.T-CON Board
- 3.3V Buck Converter
- 1.5V Buck Converter
- 1.2V Buck Converter
- 5V Buck Converter
To monitor the health of the 12V line, a voltage divider circuit is used, which sends a reference voltage (~2.1V) to the system IC. If this reference voltage is missing or incorrect, the system IC triggers a protection shutdown—resulting in the 2 blink error.
Step-by-Step Solution: Tracing the Faulty Resistor
Here’s how I diagnosed and fixed the issue:
1. Set your multimeter to continuity (buzzer) mode
2. Place one probe on the 12V power line
3. With the other probe, start checking resistors on the mainboard
4. I located a pair of resistors showing continuity to 12V and GND
One side of resistor A was connected to 12V
One side of resistor B was connected to GND
The midpoint between these two resistors was the reference signal going to the system IC
5. Upon testing, I found one of the resistors was faulty
- After replacing the damaged resistor with the correct value, the TV powered up successfully and the 2 blink error was resolved
(I will share the exact resistor values in the image attached with this post.)
Conclusion
The 2 blink error in Sony KDL-46HX750 can often be traced to a faulty voltage divider resistor on the mainboard. With basic tools like a multimeter and proper understanding of power line behavior, this fault can be easily diagnosed and fixed.
© Shaukat Ali – Sony LED TV Repair Center Lahore
This article is for educational and informational purposes only. All content, images, and technical explanations are based on the personal experience and research of Shaukat Ali. Reproduction, publication, or use of this material without permission is strictly prohibited. All rights reserved.
“Every piece of content published on this website is personally written by me, based on over 30 years of hands-on experience in LED TV repair.”
Shuakat ALI