원문 게시자: lkvee ,
Sharp LC-32LB261U generates blinking red LEDs but no backlighting
Red LED blinks 8 times before turning steady blue, but I see the "No Signal" image without backlighting. At CN9101, I get these readings on steady red LED (standby): NC (Pins 8 & 16) gives 0 volts +12V (Pins 7 & 15) gives 12.59V +12V (Pins 6 & 14) gives 12.59V +12VAU (Pins 5 & 13) gives 12.47V GND (Pins 4 & 12) gives 0V GND (Pins 3 & 11( gives 0V NC (Pins 2 & 10) gives 0.057V DIM (Pin 1) ON/OFF (Pin 2) gives 0V At CN9101, I get these readings on steady blue LED (ON): NC gives 0V +12V gives 12.58V +12V gives 12.58V +12VAU gives 12.33V GND gives 0V GND gives 0V NC gives 3.35V DIM ON/OFF gives 2.964V At CN8101, I get these readings during steady blue LED (ON): VLED+ gives 12.38V VLED+ gives 12.38V N/A gives 0V N/A gives 0V LED1 gives 0V LED1 gives 0V Three filter caps spec'ed for 56uF and 450V give these readings: C9103, C9102, and C9101 give 0V when power is disconnected C9103, C9102, and C9101 give 166V when LED is steady red (standby) C9103, C9102, and C9101 give 166V when LED is steady blue (ON) The service manual from Elektro Tanya offered a flow chart with one decision diamond asking whether the TV's generating getting 12V and 19.5V If not, then replace the power board. CN9100 but not CN9101 refer to 19.5V The TV has changed behavior. The power LED with blink red twice, but will not turn blue. I know I was less than careful with the needle probes and shorted some pins at CN9101 (I saw a little blue spark). I'm focused on the power board or a possible open circuit in the LEDs. How should I go forward?