Just fixed this 22" Samsung, the 13V from power supply is OK, Power supply for the inverter is OK, I can force the backlight on OK, but the main board has no 5V standby, no indicator light.
Download the service manual from ELEKTROTAYA and start checking the voltage on the 5V standby switching power supply section. U201 has the 13v input on pin 8 but I have no output on C221. I suspect bad IC but decide to do some resistance checking first since it has many MLLC (Multi Layer Ceramic Cap) around the circuits. The resistance reading on pin 7 was 2.3K which seems to be way too low since it has 30K (R216) and C212 (0.22uf 25v) to ground. I remove the C212 and check the resistance again, now it read around 30K. Check the leakage resistance of C212, it shows 2.4K.
So I replaced the C212, now I have my 5V and red power light, TV fires up and works again.
Download the service manual from ELEKTROTAYA and start checking the voltage on the 5V standby switching power supply section. U201 has the 13v input on pin 8 but I have no output on C221. I suspect bad IC but decide to do some resistance checking first since it has many MLLC (Multi Layer Ceramic Cap) around the circuits. The resistance reading on pin 7 was 2.3K which seems to be way too low since it has 30K (R216) and C212 (0.22uf 25v) to ground. I remove the C212 and check the resistance again, now it read around 30K. Check the leakage resistance of C212, it shows 2.4K.
So I replaced the C212, now I have my 5V and red power light, TV fires up and works again.
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