I have a Sharp model LC-60LE630M that has no backlight.
When connected to wall socked and switched on, the red standby light is on. Pressed the power button, the green light is on for ~10sec then start flashing red light 1 time slowly.
There is no picture, no sound, and no light. But with a torch light, can still see the no-signal fizzle pattern.
I have tried the "forced on" combinations like pressed and hold Vol+ and ChnDown, and Input and Vol- buttons , no effect..
I disassembled the TV to check on the led strips. There are 4 strips of 60 leds each, 2 each at top and bottom edges. Using DMM in Diode mode, each led is tested good showing 2.5V on DMM. There are 1-3 bad leds on each of the strip, which I removed but shorted the path since I have no replacement leds. Reason for shorting it is because the leds are in series within the strip, and a open led will rendered all the leds behind it not light up..
Reassembled and re-tested - still the same.
I have then check the voltages of the power board, DPS-165Hp-2A:
PD Connector Pins Stand-by Powered On
PD1 – PNL12V 0.01V 11.87V
PD2 – PNL12V 0.01V 11.87V
PD3 – GND 0.01V 0.00V
PD4 – GND 0.01V 0.01V
PD5 – UR13.2V 0.01V 12.88V
PD6 - UR13.2V 0.01V 12.86V
PD7 – UR13.2V 0.01V 12.88V
PD8 – UR13.2V 0.01V 12.86V
PD9 – GND 0.01V 0.00V
PD10 – GND 0.01V 0.01V
PD11 – GND 0.01V 0.01V
PD12 – GND 0.01V 0.01V
PD13 – AC_DET 3.10V* 3.10V
PD14 – PS_ON 0.00V 3.63V
PD15 – BU5V 5.05V 5.05V
PD16 – PNL_POW 0.00V 3.18V
PD17 – N/C 0.50V** 0.98V**
PD18 - N/C 0.01V 1.68V**
PD19 – DIMMER 0.01V 0.01V
PD20 – N/C 0.01V 1.42V**
PD21 – OFL 0.00V 0.00V
PD22 – ERROR 0.13V 0.03V
PD23 – N/C 0.40V** 1.13V*
PD24 – STB 0.01V 0.00V
*voltage dropped to 0V in few seconds
** voltage dropping very slowly
And with black probe on chassis, red probe on each of LED1+, LED1- to LED4+ and LED4-, all showing 0 volt. The 2 big capacitors around them read 208Vdc.
And disconnecting the LED connector, the reading on the PD pins remain unchanged.
Kindly help to point of if anything obviously wrong or bad, or need further investigation.
Thank you.
When connected to wall socked and switched on, the red standby light is on. Pressed the power button, the green light is on for ~10sec then start flashing red light 1 time slowly.
There is no picture, no sound, and no light. But with a torch light, can still see the no-signal fizzle pattern.
I have tried the "forced on" combinations like pressed and hold Vol+ and ChnDown, and Input and Vol- buttons , no effect..
I disassembled the TV to check on the led strips. There are 4 strips of 60 leds each, 2 each at top and bottom edges. Using DMM in Diode mode, each led is tested good showing 2.5V on DMM. There are 1-3 bad leds on each of the strip, which I removed but shorted the path since I have no replacement leds. Reason for shorting it is because the leds are in series within the strip, and a open led will rendered all the leds behind it not light up..
Reassembled and re-tested - still the same.
I have then check the voltages of the power board, DPS-165Hp-2A:
PD Connector Pins Stand-by Powered On
PD1 – PNL12V 0.01V 11.87V
PD2 – PNL12V 0.01V 11.87V
PD3 – GND 0.01V 0.00V
PD4 – GND 0.01V 0.01V
PD5 – UR13.2V 0.01V 12.88V
PD6 - UR13.2V 0.01V 12.86V
PD7 – UR13.2V 0.01V 12.88V
PD8 – UR13.2V 0.01V 12.86V
PD9 – GND 0.01V 0.00V
PD10 – GND 0.01V 0.01V
PD11 – GND 0.01V 0.01V
PD12 – GND 0.01V 0.01V
PD13 – AC_DET 3.10V* 3.10V
PD14 – PS_ON 0.00V 3.63V
PD15 – BU5V 5.05V 5.05V
PD16 – PNL_POW 0.00V 3.18V
PD17 – N/C 0.50V** 0.98V**
PD18 - N/C 0.01V 1.68V**
PD19 – DIMMER 0.01V 0.01V
PD20 – N/C 0.01V 1.42V**
PD21 – OFL 0.00V 0.00V
PD22 – ERROR 0.13V 0.03V
PD23 – N/C 0.40V** 1.13V*
PD24 – STB 0.01V 0.00V
*voltage dropped to 0V in few seconds
** voltage dropping very slowly
And with black probe on chassis, red probe on each of LED1+, LED1- to LED4+ and LED4-, all showing 0 volt. The 2 big capacitors around them read 208Vdc.
And disconnecting the LED connector, the reading on the PD pins remain unchanged.
Kindly help to point of if anything obviously wrong or bad, or need further investigation.
Thank you.
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