TCL L32S6500 Power Supply Fault Repaired
Let’s learn how to solve its dead fault How to Repair Dead Fault TCL L32S6500. When this LED TV came to me, it was completely off; its red light was not even showing. Now either its power supply was faulty or there was a fault in some other section of its main board. This could be known only by diagnosing it. By the way, my first thoughts were that the power supply was faulty. I took some time from the customer and put the set on hold until the next day.
TCL L32S6500 power Supply repair solution
The next day I opened this set in the workshop lab and first checked its power supply, which was inside the main board. I first examined the board carefully and realized that it had been tampered with by a technician because the soldering in its power supply area was very poor. Well, I checked its 12-volt supply, and it was not there. I checked its main fuse, and it was fine. Then I checked its bridge rectifier, and it was fine. I checked its main MOSFET and its related parts, i.e., the resistor on the gate of the MOSFET, and it was also fine.
Power Supply fault diagnosis
In this model of TCL, the OB2273 IC is used in the power supply. It is a six-pin IC. It is a very simple circuit. Once you have a clear understanding, we can proceed to fault finding. As a precaution, I first changed its IC, although I thought that the technician had installed a new IC before me. Now I opened the resistance of this circuit and started checking it with a multimeter. The two resistors connected to pin number 4 of the main IC were found to have open values.
These resistances are current sensing. Now I did not have the values of these resistances. So I installed a 470-ohm resistor in place of both of them and turned on the power supply and checked. Now the twelve-volt output was coming, but it was blinking, that is, it was going up and down. This problem is of the feedback circuit. We will see this separately. This feedback comes from the optocoupler.
TCL L32S6500 Feedback Circuit Repair
TL431 is a Zener-type IC that works in conjunction with an optocoupler and provides feedback to an isolated power supply. The main role in this circuit is played by the TL431 IC. This IC has three pins: anode, cathode, and reference pin. The reference voltage is set by placing a voltage divider resistor on its reference pin. Now it depends on the circuit whether two resistors are used in the voltage divider or two. In this model,
Three resistors are used in series. In my case, these resistors were bad. Now I did not even have their value. So, according to the formula, I used two resistors here, which you can understand as R1 18K and R2 4.7K, and I put a jumper in the place of the third resistor in the circuit. By doing this, the reference voltage of the IC was completed, which is 2.5V. Now I have When I switched on the power supply, my fault was fixed.
Key Points Summary
- The TCL L32S6500 power supply section is built inside the main board.
- The 12V output was missing while the fuse and bridge rectifier were OK.
- The power supply used an OB2273 IC, and its related resistors were found open.
- After replacing the faulty resistors, the 12V output appeared but was fluctuating.
- The issue was traced to the feedback circuit involving TL431 and an optocoupler.
- Faulty resistors in the feedback path were replaced with 18K and 4.7K values.
- After replacement, the power supply became stable and fully functional.
Conclusion
How to Repair Dead Fault TCL L32S6500 You saw how we diagnosed the dead fault of this model and fixed this fault step by step. It was a difficult task. It was very meticulous. If we had taken the option of replacing the main board only, it would have been a very easy task. But we used our skills and solved this difficult fault. I would also request of my fellow technicians that you guys should focus on chip-level repairing. Replacing the entire board is not a miracle.
Q&A
Q1:How to fix TCL TV on power?
It depends on the model. Usually, the power supply of a TCL LED TV is repaired, as you saw in our article, where we fixed a power supply in very bad condition.
Q2:How to fix faulty power Supply on TCL TV?
Check the main fuse, and test the MOSFET and related IC. Don’t forget to read our article for the rest of the details.
Q3:What is the common problem of TCL TV?
The common reasons a fuse may be open are the MOSFET may be faulty, or the main IC may be faulty.
4:Can TCL TV be repaired?
It is possible to repair their power supply, but you will need the help of a professional technician.
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Shaukat Ali has over 30 years of experience in LED TV repair, specializing in chip-level repair work. He is an expert in Sony LED TVs, and also repairs other major brands like Samsung, TCL, Orient, and Haier. His expertise includes display panel faults, motherboard issues, power supply circuits, T-Con, and HDMI faults. Based in Lahore, he shares real-time fault finding cases from daily repair work to help technicians and learners with practical experience.
📞 Contact: +92 321 4066054