Sharp LC-70le660u shuts off power light blinks

[nwcs]

I need some help on this one. Original problem was the backlight would flash then the power led would go out then start blinking a slow single blink. I now get it to turn on with a picture but when it gets past the sharp splash screen the tv shuts off like before and the single slow blink starts. Voltages are correct when the tv is on but I am not sure what they should be at PWM1, Dimmer and OFL. Any way looking at the picture it does not appear to have any bad led's so I think that is out of the question but I know these tv's are known for bad tab's but I am leaning towards a bad main board. Has anyone had any experience with this issue on these tv's.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

I am back looking at this tv and would like to know if anyone can help with some voltages. I need to know what pwm1 and pwm2 should be as well as ofl. They all read 0V and I believe they should have some value. Also an update I did pull the panel off and tested the led's and they are all working.

[budm]

Re: Sharp LC-70le660u shuts off power light blinks

Can you provide the Voltage readings of all the pins?
PWM can be between 1vdc~4VDC range. I do not know what OFL is.

[budwich]

Re: Sharp LC-70le660u shuts off power light blinks

disconnect one of the tcon cables (going from tcon to panel) and see what happens. Do the same "test" with the other. Go from there.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Wow I never thought of that. I disconnected the cables to the panel from the tcon and it now lights up. I then hooked up each side separately and it would light up. I then connected both cables and it lights up for maybe 30 seconds then shuts off. I do not get anything to display though. And the one light error blink appears to be gone.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Sorry, I talked too soon. It does display a picture and now it shuts off and gives the one blink code. I will try to reset it and see what that does.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

The voltages are as follows:
pin 1 and 2 are 12v, pin 3 and 4 0v, pin 5 thru 8 13v, pins 9 thru 12 0v, pin 13 and 14 are 3v, pin 15 is 3.3v pins 17 and 18 are 0v, pin 19 is 3v, pins 19 thru 23 are 0v and pin 24 is 3v.

[budwich]

Re: Sharp LC-70le660u shuts off power light blinks

OK... I think... sorry can't follow your "observations"... maybe restate them.
further when you have one side disconnected, is there a picture on the other side (feed some thing in or hit "menu").... do the same with the other side. Post pictures of your results if you see something.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Yes there is a picture on the other side and when the picture comes on the tv shuts off and gets the one blink code. is is too quick to post a picture of it though.

[budwich]

Re: Sharp LC-70le660u shuts off power light blinks

ok... is the response the same for either cable disconnect?
I re-read your post / observations. With just one cable disconnected, does the tv stay on? Don't worry about connecting both at this point.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Yes the same no matter which side is disconnected. I think it stays on longer with both connected but not much longer. after the sharp logo it goes to what I believe is the multimedia logon and then shuts off.

[budwich]

Re: Sharp LC-70le660u shuts off power light blinks

you need to provide a better format for your voltage readings...
pin x voltage y ... label bl-on whatever.... people don't know what pins are what unless you tell them.

... and when the readings were taken... ie. with display / after it dies / etc. In your case, you need to get them before the flashing code starts and then another set there after.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Sorry about that. Here they are

pin 1 and 2 pnl 12v, pin 3 and 4 gnd, pin 5 thru 8 ur13v, pin 9 thru 12 gnd, pin 13 ac_det3v, pin 14 ps_on3v, pin 15 BU5V, pin 16 pnl_pow 3.29v, Pin 17 pwm1 0v, pin 18 nc, pin 19 dimmer 3v, pin 20 nc, pin 21 ofl 0v, pin 22 error 0v, pin 23 pwm2 0v and pin 24 stb 3v.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Readings were taken when the display is on. I did not take the readings with the tcon disconnected. Maybe I should since it stays on longer. The voltages do start dropping when the flashing starts.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

Thanks budwich for all of your help. The customer got tired of waiting so I no longer have the tv for testing. I just wish I could have narrowed the problem down. I am still pretty sure the panel is bad.

[BookWormStud]

Re: Sharp LC-70le660u shuts off power light blinks

I have the same problem but my TV is panasonic. In my case backlights are flashing ON and OFF. I did the flashlight test with backlight disconnected the Panel stays ON.

OP could have made the TV stay on longer if he could somehow be able decrease the backlight and brightness settings. That's what I did and now it stays ON with backlight flashing but TV doesn't go to standby.

If OP and Repliers could help me. I'd post more info about my TV.

[dskall]

Re: Sharp LC-70le660u shuts off power light blinks

I would say you have bad led's breaking down under load

[BookWormStud]

Re: Sharp LC-70le660u shuts off power light blinks

Is there any way to jump the wires and turn on the Backlights without giving any power Main Board. Cause I read somewhere you could but couldn't understand how to do it.

Image shows the O/G post about jumping wires.

I have the schematics for my TV if anyone could tell me I'd grateful.

[nwcs]

Re: Sharp LC-70le660u shuts off power light blinks

I hope this will help someone with the same problem I had. The customer brought the TV back to me to recycle and as luck would have it I had the same TV in with a broken panel. I replaced the main board from the broken screen tv and now the TV works fine. Thanks all who helped.