Changhong plasma burning Z plate, do not need to change the Z plate and Y plate, it is not difficult to repair, look at me. - appliance repair - Huaqiang Electronic Network

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

X3S026000B91H-Z

I recently repaired two Changhong 42638 plasma TVs, both of which had burned Z boards. One was fixed last year, and the other just a few days ago. I remember reading online that some technicians recommend replacing both the Z and Y boards together. So, I bought three boards: Z, Y, and a buffer board. After replacing all of them, I found that the new Z board had failed during boot. I ended up returning it and lost around 50 yuan in the process. Then, I informed the user that this model is often associated with cracked screens and that the unit wasn’t repairable here. A few days ago, I received another Changhong 42638 plasma from a customer who mentioned the relay was making noise. I immediately suspected a burned board. Upon checking, I confirmed that the Z board was indeed damaged. This time, instead of buying new parts online, I decided to try repairing the board myself. I identified that the Z board failure was usually caused by two burnt RJH30E2 components. Using a magnifying glass, I noticed some cracks around the solder joints on the board. Considering the high power consumption and heat generated by plasma TVs, I realized that cold solder joints were more common than in CRT TVs. I ordered six RJH30E2s from TB and replaced two of them. Then I took out the Y board and fully repaired the heat sink, several power transistors, inductors, and capacitors. I also sprayed WD40 on all flexible cables connected to the logic board to prevent corrosion. To ensure safety, I connected a clamp meter in series with each output from the power board to the Y board. This allowed me to monitor the current and shut it down if needed, preventing any further damage. The TV started normally, with a current draw between 0.4-0.6A. The screen worked fine, and the boot music played as expected. I was really happy with the result. I quickly applied the same method to a Changhong 42738 plasma I had repaired earlier. I replaced the two RJH30E2s on the Z board and re-soldered some components on both the Z and Y boards. It was a large-scale repair, but it worked well. Looking at the worried customers with burning boards, I felt confident that my approach could help others too. You can try similar repairs if you're comfortable working with electronics. The image below is a screenshot from a video I recorded on my phone, so the resolution isn't very high.