Sharp LC 70LE640U LCD TV power problem

[tech2014]

I have a sharp LCD tv where the power led flashes slowly twice, the fast 5 times. The code is a 12v panel failure. Is this voltage produced on the power supply or main board?

I get 12v for a bit then it shuts down. When testing p/s outside tv, I don't get 12v but all other voltages.

[Doc38343]

Re: Sharp LC 70LE640U LCD TV power problem

Would try to follow the 12V pin's trace back to the mosfet that controls it. It may be hard to do. I also would test all the diodes on the power supply board (out of the unit and lift one leg if you are able) If you had the 12V on the PS but not on the panel follow the cables back from the panel and on some main boards there can be a voltage regulator as well but usually this would be the PS board just my guess I'm no expert, just trying to help.

[budm]

Re: Sharp LC 70LE640U LCD TV power problem

Is this your Power supply board?
http://www.shopjimmy.com/sharp-runtk...led-board.htm#

The main board sends the PNL_POWER on signal (>2VDC) to the power supply board 'PD' connector pin 16, this signal turned on the switched power MOSFET Q7120 on the power supply board which it then sends out the 12VDC to the connector 'PD' pin 1-2 PNL_12V, this output then go to the T-CON board on the panel.
If the T-CON does not get the 12VDC then the T-CON will send the error signal to the main board and generates the error code.

[tech2014]

Re: Sharp LC 70LE640U LCD TV power problem

I have replaced all the boards on this tv and still getting the 2 slow flashes and 5 quick flashes. I reset it 4 times and no change. Does this mean its a bad LCD panel lamp.

[johnboy1313]

Re: Sharp LC 70LE640U LCD TV power problem

1-1 is a panel lamp failure, 2-5 is likely a bad panel. Try unseating the ribbons from the tcon to the panel one at a time and see if it will power on.

[tech2014]

Re: Sharp LC 70LE640U LCD TV power problem

Yes I removed the ribbon cables from the t-con to the panel and the led now stays solid, so I guess the panel is shot. thanks johnboy.

[tom66]

Re: Sharp LC 70LE640U LCD TV power problem

Another LE6xx/LE8xx series Sharp with bad LCD panel.
Sigh.