Konka LCD TV LC24FS66DC button is not easy to use - are "glue" to blame - appliance repair

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I recently worked on a Konka LCD TV model LC24FS66DC, with motherboard number 35015272. The main issue was that the buttons were unresponsive and sometimes the TV would power on but immediately go into standby mode with the message: "You have entered the standby state, don't forget to turn off the power." That wording is a bit confusing — maybe it should be "Your TV has entered the standby state" instead? Anyway, let's get into the details. First, I checked the button board. The voltage and resistance of each button were normal. Using a multimeter in X10K mode, there was no leakage detected. The buttons looked new, no signs of rust or damage. The input voltage at the button socket was 3.3V, so it wasn’t a problem with the buttons themselves. Next, I tested the main board. The 12V and STB3.3V (which measured around 3.4V) were both within range. The reset circuit output was also normal, showing a high-level pulse when powered on. However, when I checked the voltage at pin 130 of the MCU, it read 0V — that was a big clue! I took a look at the schematic and found that resistor R561 (100Ω) might be open. There was a lot of gray glue around the XS644 connector, so I carefully removed it. After cleaning, R561 was finally visible. Measuring its resistance showed infinity, confirming it was open. The trace from R561 to the MCU pin was intact, so replacing R561 fixed the issue. Here are the relevant diagrams: Konka 35015272.pdf Another case involved a Changhong LT4024 TV. It would power on and go into standby, but the screen wouldn’t light up. I checked the power supply and noticed that the 24V output spiked briefly and then dropped to zero. The start signal was normal, but the optocoupler for the 24V regulator had no voltage on pins 1 and 2. That indicated a loss of power to the optocoupler, causing the power supply to shut down. I removed the white glue around the optocoupler and found resistor R863 was open. Replacing it resolved the issue. I've also repaired two plasma TVs with similar issues — the backlight constant current boards had open resistors, which caused black screens. In both cases, the faulty resistors had a layer of glue on them. It’s not a coincidence. Could it be related to heat dissipation, thermal expansion, or stress over time? These cases highlight how small components can cause big problems, especially when they're hidden under glue or difficult to access. It’s always worth checking those hard-to-reach parts first. Finally, after all these repairs, I just want to say — Konka, please update your message! "You have entered the standby state" sounds a bit awkward. Maybe "Your TV has entered the standby state" would be better. Just a friendly suggestion.