Skyworth color TV 6D90 movement 29T61HT red light is not on the fault repair example - Appliances

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This is a repair case of the Skyworth color TV model 6D90, with the 29T61HT board. The issue was that the red light would not turn on. When measuring the +B voltage, it was around 40V. After disconnecting the standby control circuit, the voltage rose to 140V. The 5V power supply on the digital board was normal. Using an oscilloscope, I checked the SDA and SCL signals of the memory, but no data exchange waveform was observed during normal startup. Instead, a DC voltage of about 4.6V was displayed. Based on this, the failure was traced to the digital board, possibly involving the memory, CPU, or the data line "plug-in". Following the principle of starting with the easiest solutions first, I disconnected the resistor connected to the LM1269 chip on the SDA/SCL line. After powering up again, it became clear that the LM1269 had been damaged. Normally, if there's a failure in the CPU "plug-in" block affecting SDA/SCL, there should be a "busy" signal due to continuous data exchange. However, in this case, no such behavior was observed. This suggests that the issue might have been more specific, possibly related to the memory or its interface rather than the CPU itself.