Sharp LC-60LE600U turns off after turning on

[mikeroq]

I have a Sharp LC-60LE600U TV. So far I haven't found a service manual for it.

The LED indicator will light up white and then turn off after about 10 seconds.
I noticed when probing the voltages right before the indicator would go off there would be a short buzz and I could see the LEDs light up for a second at the edge of the panel.

PIN VOLTAGE ON VOLTAGE AFTER LED TURNS OFF
PD1 – PNL12V 12V 0V
PD2 – PNL12V 12V 0V
PD3 – GND 0V 0V
PD4 – GND 0V 0V
PD5 – UR13.2V 0V 0V
PD6 - UR13.2V 13.2V 0V
PD7 – UR13.2V (N/C) 0V 0V
PD8 – UR13.2V (N/C) 0V 0V
PD9 – GND 0V 0V
PD10 – GND 0V 0V
PD11 – GND 0V 0V
PD12 – GND (N/C) 0V 0V
PD13 – AC_DET 3.3V 2.5V
PD14 – PS_ON 2.08V 0V
PD15 – BU5V 5.04V 5.04V
PD16 – PNL_POW 0V 0V
PD17 – PWN1 0V 0V
PD18 - N/C 0V 0V
PD19 – DIMMER 0V 0V
PD20 – N/C 0V 0V
PD21 – OFL (N/C) 0V 0V
PD22 – ERROR 3.29V 0V
PD23 – PWM2 (N/C) 0V 0V
PD23 – STB 0V 0V

L1-1 LED1+ 11V
L1-3 LED1- 83V
L1-5 LED2+ 11V
L1-7 LED2- 83V
L1-9 LED3+ 11V
L1-11 LED3- 76V
L1-13 LED4+ 11V
L1-15 LED4- 83V


I tired powering it one with one of the cables disconnected from the TCON board. With either ribbon cable disconnected the LED would go out in just a couple seconds. I unplugged the LED power connector from the power board and when turning on the LED was flashing. I didn't appear to have a pattern other than just a steady blink on and off.

I'm leaning towards maybe a bad power board but I am not sure. I want to be more sure before I buy a power board or any other board.

Thanks for the help.

[nomoresonys]

Re: Sharp LC-60LE600U turns off after turning on

With power unplugged, unhook cable from powerboard to mainboard, plug power cord back in, see if backlights come on and stay on, just a little test, if the backlights don't come on then go ahead and recheck your voltages on powerboard with that cable unhooked see what you have.

[nomoresonys]

Re: Sharp LC-60LE600U turns off after turning on

Do you know the history of this one?

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

I tried with the cable unplugged from the main board. I don't think anything turned on the only voltage I saw was 5V on the BU5V. Do I need to jumper the power board on?

All I know is that it was working normally until it started doing this.

[neilc6]

Re: Sharp LC-60LE600U turns off after turning on

L1-1 LED1+ 11V
L1-3 LED1- 83V
L1-5 LED2+ 11V
L1-7 LED2- 83V
L1-9 LED3+ 11V
L1-11 LED3- 76V <<<<<<<
L1-13 LED4+ 11V
L1-15 LED4- 83V

Looks like shorted LEDs on that section of edge lit strips. An LED tester would confirm.

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

Looks like shorted LEDs on that section of edge lit strips. An LED tester would confirm.

Like this? https://www.amazon.com/SID-LED-Backl...CXJWHWVQKPWC11

Is there any way to confirm without a tester?

[budm]

Re: Sharp LC-60LE600U turns off after turning on

Pin voltage on voltage after led turns off
pd1 – pnl12v 12v 0v
pd2 – pnl12v 12v 0v
pd3 – gnd 0v 0v
pd4 – gnd 0v 0v
pd5 – ur13.2v 0v 0v
pd6 - ur13.2v 13.2v 0v
pd7 – ur13.2v (n/c) 0v 0v
pd8 – ur13.2v (n/c) 0v 0v
pd9 – gnd 0v 0v
pd10 – gnd 0v 0v
pd11 – gnd 0v 0v
pd12 – gnd (n/c) 0v 0v
pd13 – ac_det 3.3v 2.5v
pd14 – ps_on 2.08v 0v
pd15 – bu5v 5.04v 5.04v
pd16 – pnl_pow 0v 0v
pd17 – pwn1 0v 0v
pd18 - n/c 0v 0v
pd19 – dimmer 0v 0v
pd20 – n/c 0v 0v
pd21 – ofl (n/c) 0v 0v
pd22 – error 3.29v 0v
pd23 – pwm2 (n/c) 0v 0v
pd23 – stb 0v 0v. STB = BL-ON

l1-1 led1+ 11v
l1-3 led1- 83v
l1-5 led2+ 11v
l1-7 led2- 83v
l1-9 led3+ 11v
l1-11 led3- 76v
l1-13 led4+ 11v
l1-15 led4- 83v

1) Are you sure the STB (BL-ON) did not go up to more than 3VDC when TV is first turned on? You cannot have backlights on if that STB control Voltage is not present.
2) It looks like you count the LED connector wrong, you cannot have the LED - pins to have higher Voltage than the LED + pins because the LED+ pin are the Anode pins which are fed by the Boost converter circuits, the LED - pins are the Cathode return.
3) The 80V readings are the feeding Voltage to the boost converter, so if STB control Voltage is not present then you will not see the LED+ to go over 100V.
4) You shows pd16 – pnl_pow 0v 0v, pd1 – pnl12v 12v 0v. If you truly have pnl_pow 0v at turn on, then no way you can have PNL12V.
5) You also have other missing control Voltages.
6) Are you sure you are not seeing error blinking code?

Is this your board?
https://www.shopjimmy.com/sharp-runt...led-board.htm#

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

1) Are you sure the STB (BL-ON) did not go up to more than 3VDC when TV is first turned on? You cannot have backlights on if that STB control Voltage is not present.
2) It looks like you count the LED connector wrong, you cannot have the LED - pins to have higher Voltage than the LED + pins because the LED+ pin are the Anode pins which are fed by the Boost converter circuits, the LED - pins are the Cathode return.
3) The 80V readings are the feeding Voltage to the boost converter, so if STB control Voltage is not present then you will not see the LED+ to go over 100V.
4) You shows pd16 – pnl_pow 0v 0v, pd1 – pnl12v 12v 0v. If you truly have pnl_pow 0v at turn on, then no way you can have PNL12V.
5) You also have other missing control Voltages.
6) Are you sure you are not seeing error blinking code?

Is this your board?
https://www.shopjimmy.com/sharp-runt...led-board.htm#

I must have not made good contact on some of the readings. I was backprobing the female connector.

1) PD24 STB hits 3.06V then the backlight flashes on for a second.
2) I have the LED pinout backwards Should be:

L1-15 LED4- 11V 0V
L1-13 LED4+ 83V 0V
L1-11 LED3- 11V 0V
L1-9 LED3+ 83V 0V
L1-7 LED2- 11V 0V
L1-5 LED2+ 76V 0V
L1-3 LED1- 11V 0V
L1-1 LED1+ 83V 0V

3) None of the LED+ read over 83V

4) PD16 PNL_POW jumps up to 3.26V right before the backlight flashes. PD1 PNL12V and PD2 PNL12V ramp up to 12V then stay at 12V for a few seconds then the backlight flash happens then drop to 0V.

5) What other voltages? Here is an updated reading:

PIN VOLTAGE ON
PD1 – PNL12V 12V
PD2 – PNL12V 12V
PD3 – GND 0V
PD4 – GND 0V
PD5 – UR13.2V 13.12V
PD6 - UR13.2V 13.12V
PD7 – UR13.2V (N/C) 13.12V
PD8 – UR13.2V (N/C) 13.12V
PD9 – GND 0V
PD10 – GND 0V
PD11 – GND 0V
PD12 – GND (N/C) 0V
PD13 – AC_DET 3.3V
PD14 – PS_ON 2.08V
PD15 – BU5V 5.04V
PD16 – PNL_POW 3.26V
PD17 – PWN1 0V
PD18 - N/C 0V
PD19 – DIMMER 0V
PD20 – N/C 0V
PD21 – OFL (N/C) 0V
PD22 – ERROR 3.29V
PD23 – PWM2 (N/C) 0V
PD23 – STB 3.06V

L1-15 LED4- 11V
L1-13 LED4+ 83V
L1-11 LED3- 11V
L1-9 LED3+ 83V
L1-7 LED2- 11V
L1-5 LED2+ 76V
L1-3 LED1- 11V
L1-1 LED1+ 83V


6) I pulled the LED indicator board out so I could point it towards me since the TV is laying down. The only time I had a flash was when I unplugged the L1 LED connector at the top of the board and supplied power to the TV. I have it hooked up to a surge protector to turn it on and off. When I turn it on the 3 LEDs turns on. Then a few seconds later I see the backlight turn on for a second then turn off. Then a couple seconds later the 3 LEDs light turns off.

And yes that is the power board.

Thanks for your help.

[budwich]

Re: Sharp LC-60LE600U turns off after turning on

was it always hooked to a surge protector? If so, try another outlet without a protector.

As budm indicates, it is likely that the 2nd string has a shorted led resulting in lower voltage but also higher current which might be triggering protection in the set.

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

I'm not sure of the history before I got it so I don't know if it was hooked up to a surge protector. I had this plugged into the outlet directly before adding the surge as a means to turn if off and on easily. It's doing the same thing the people I got it from were reporting that it would light up and turn back off.

[nomoresonys]

Re: Sharp LC-60LE600U turns off after turning on

PD22 -ERROR 3.29v, isn't that a backlight sos?

[budm]

Re: Sharp LC-60LE600U turns off after turning on

PD22 Error (Backlights error): Good = >3V, bad = drops down to <1V.
The report on
Post 1 shows: PD22 – ERROR 3.29V 0V.
Post 8 shows: PD22 – ERROR 3.29V
So I do not know if it does go down to 0V or not for sure at this point.
He should also see blinking error codes.

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

It ramps up to 3.29V then stays steady until the backlight flashes on and then the tv turns off.

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

He should also see blinking error codes.

It's the ^ shaped light on the front right?

[budm]

Re: Sharp LC-60LE600U turns off after turning on

Service manual, may be close enough for error codes.
Right now this reading looks suspicious:
L1-15 LED4- 11V
L1-13 LED4+ 83V
L1-11 LED3- 11V
L1-9 LED3+ 83V
L1-7 LED2- 11V
L1-5 LED2+ 76V
L1-3 LED1- 11V
L1-1 LED1+ 83V

[mikeroq]

Re: Sharp LC-60LE600U turns off after turning on

So most likely there is a failure on that LED strip? Does it sound like the power board is alright?

[neilc6]

Re: Sharp LC-60LE600U turns off after turning on

Like this? https://www.amazon.com/SID-LED-Backl...CXJWHWVQKPWC11

Is there any way to confirm without a tester?

You can confirm without a tester but you would need to remove the panel and the clear plastic diffuser. The tv should turn on without the panel attached and you can observe the led strips light up. Sometimes it is obvious they have failed if they show burnt areas.

[budm]

Re: Sharp LC-60LE600U turns off after turning on

At this point it does look like LED issue in LED 2 string, this is where the LED tester come in handy so you can read the Vf of each LED string to verify by comparing the readings of all 4 strings.
You can also swap the LED 1 string's wires with the LED 2 string's wires to see if the reading of LED string #2 will follow or not. It looks like LED string #2 may have some shorted out LED's.

[budm]

Re: Sharp LC-60LE600U turns off after turning on

BTW, what is the P/N of that SMD LED driver IC7201?
MP24830?