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Discussion Starter · #1 ·
Right now, my TV is flashing green light after a convergence repair. I have just replaced the DM caps and I still have the same problem. I'm hoping to find some help to keep my Mitsubishi WS-65869 going for another year or more until OLED's mature a bit!

The initial problem was that the TV would turn off immediately after turning on. I ran the diagnostic an it gave me Error Code 22 (short protect). Both pico fuses (F904 & F905) were blown. I replaced the convergence chip with a new spare I had. I also replaced the two fuses. All of the resistors in the convergence circuit appeared to be in good shape. I had some burn marks on the board under a couple of the core-ferrite chips. However, they tested fine with a multi-meter. I think the core-ferrites are just for noise suppression anyway. Everything else on the board looked to be in good order, at least visually.

After plugging everything back in, checking connections 4-5 times, I turned on the TV. The TV started flashing green, but never stopped :crying2:.

I replaced the DM capacitors some time ago with 1000uf 105C 16V capacitors. However, I went ahead and replaced and upgraded the capacitors with Panasonic 1000uf 105C 35V capacitors (tight fit) thinking that old ones were bad as I installed some low end ones last time. The TV is still flashing green continuously. :help:

I have heard that a faulty EEPROM could also cause the flashing. Is there a way to check? What would happen if I remove the board and power the TV on?

I guess my next step is to go through the board and test voltages. Is there a certain order or process to test? Any other suggestions?
 

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Discussion Starter · #2 · (Edited)
So I pulled out the DM unit and tested the input and output voltages. My input voltages are on PCB Power (PF) are all testing fine. Additionally the 12V (Pin 9) and 28V (Pin 11) which pass through to DM Mod (PE) are also testing fine.

All of the DM Mod pins that should be 5V (Pins 7 of PE and 6 of PD) or 3.3V (Pins 3,4 of PE and 1,3 of PD) are only showing about 1 volt. I also hear a ticking sound coming from the board.

Both fuses on the board are closed (working). Assuming the capacitors are in good working order, any suggestions?
 

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Discussion Starter · #3 ·
Making progress... I removed the DM Power Supply and tested voltages. They were showing only one volt where they should be either 5 or 3.3 volts on the DM Power outputs. I noticed some "clicking" sounds coming from the board. This morning, I was going to test voltages across some of the board components. To do this, I had the board unmounted from the case. I plugged the TV in and low and behold, the light stopped flashing and the TV turned on!!!grin2

My only thought is that somehow the solder legs on some of the components are shorting out on the case. This was probably the "clicking" sound I heard. It likely manifested due to the larger caps pushing the board down further into the tray. To remedy, there are a few longer factory components that I'll grind down a bit. I'll may also try and figure out something I can put on the try to isolate it some. Another thought is to cut out the cover above the caps which would give more space and maybe a bit of added cooling to the unit.

Now I need to attack some severe bowing issues on the screen...
 
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