For Sony TV model R6, the panel indicator light is on, but it shows the "three no" phenomenon (no picture, no sound, no power). Repair思路 E8: 1. Check if the power supply circuit is normal. 2. Inspect whether there are issues with the mainboard or its components. 3. Test the inverter and backlight system for faults. 4. Examine connections and interfaces for looseness or damage. 5. Review the possibility of a fault in the control circuit or software malfunction. (Note: Specific steps may depend on detailed technical specifications and diagnostic tools.)

### Troubleshooting思路:

The indicator light being on indicates that the secondary switch power supply and CPU are basically normal. The main power supply should be checked as a priority. Measurements taken at the rectified output terminals of T601 show no short circuit phenomena. After powering on, the +B voltage is measured to be 0V, with pin 1 of IC601 showing 286V and this voltage not disappearing for a long time after shutdown. Based on this, it can be judged that the switch power supply has stopped oscillating. Connecting a dummy load causes the +B voltage to fluctuate momentarily before returning to 0V, while the voltage across C623 is measured as 28V DC, indicating that the device enters an automatic protection state immediately upon startup. Checking the components in the protection circuit reveals them to be normal, but examining the +B voltage output circuit uncovers a leakage resistance of approximately 7.5kΩ in the capacitor C616 connected in parallel across D608.

### Repair Method:

Replacing the faulty capacitor C616 with a same model 0.1F/2kV capacitor resolves the issue.

### Symptoms:

Sony TV: The panel indicator light is on, but the TV exhibits the "three-no" phenomenon (no picture, no sound, no response).

### Source:

http://blog.163.com/sony_dianshiqrs490/