Sharp LC-40LE810UN question

[tibimakai]

Re: Sharp LC-40LE810UN question

I was alone with my 4 year old daughter and didn't have time, but later today I will measure and take pictures.

[tibimakai]

Re: Sharp LC-40LE810UN question

OK, T-con is not receiving anything.
Point
#1= 5.555V
#2= 13.04V
#3= 13.04V
#4= after like 10 sec. becomes 12.17V for a second and then drops toward 0V.
#5= 0V(alternates between + and -)
Here are the pictures:

[olegi]

Re: Sharp LC-40LE810UN question

Hi tibimakai,can you remove all cable from power supply lave only 110v ,apply PS_ON manually and see V on main caps.Post results.

[tibimakai]

Re: Sharp LC-40LE810UN question

Nothing happens.

[tibimakai]

Re: Sharp LC-40LE810UN question

I don't think this power supply is as simple as other TVs. This is probably has a smart power supply also, since the TV is a smart TV(kidding).
I see an AC detect there, I guess that one has to receive some signal too, no?

[olegi]

Re: Sharp LC-40LE810UN question

Signal (PD-9)AC-det is output signal from Q7061 to detect it they use 3rd optocoupler PC7703

[tibimakai]

Re: Sharp LC-40LE810UN question

So, what should be the next step?

[tibimakai]

Re: Sharp LC-40LE810UN question

OK, to bring back the attention I'm posting the measurements that I have at the PS connector.
So it takes a couple of seconds to turn on, as Olegi said like 10 sec.
When the TV is turned on, I have the right voltages(not sure about the PWR_POW at pin#12).
#1-2= 13.02V
#3-4= 13.02V
#5-6= 0V(GND)
#7-8= 0V(GND)
#9= 3.13V(AC_DET)
#10= 3.03V(PS_ON)
#11= 5.02V(STBY)
#12= 0.12V(PWR_POW)
When the blinking code comes up, the only voltage is left is the standby.
I know that the 400V is missing and that is most likely the problem of this TV.
I guess we have to look at the DAC002, am I right?
When the TV comes on the 168V drops to 155V and then back up to 168V when tghe code kicks in.

[olegi]

Re: Sharp LC-40LE810UN question

You said that you have bought 2nd power supply .Do you have same reading on this connector ?When you have on pin #10= 3.03V(PS_ON) there has to be ~400V on main caps.Can you tell what is the voltage on C7961A ;C7962A for first 10 sec til you get error code?

[tibimakai]

Re: Sharp LC-40LE810UN question

It was exactly the same as mine, so no reason to keep it. I will let you know about the voltages, now I'm at the beach.

[olegi]

Re: Sharp LC-40LE810UN question

here is similar schematic

[tibimakai]

Re: Sharp LC-40LE810UN question

The voltages are 13.04V and 6.38V.
Thanks for the schematics, I will have to look at them.

[Mt.Man]

Re: Sharp LC-40LE810UN question

Had a LC-40LE835U last week that uses the same power board. It also had a 2 long, 5 short error with no back lights coming on.
Turns out the panel was cracked. The TCON senses an voltage error on the panel and produces the 2 long, 5 short panel power error.

Try forcing on the TV, which should power up the back lights. On the TV touch pad, Press and hold Vol DN and Ch Up, while holding those press PWR. Do not release PWR till the icon LED lights steady then release the PWR button only but still hold the other 2. The back lights should come on.

[tibimakai]

Re: Sharp LC-40LE810UN question

Thank you, I will try it when I will be home, but I hope I don't have the same issue though.

[tibimakai]

Re: Sharp LC-40LE810UN question

Unfortunately it's not working this method, because as I plug it in it's already booting up by itself.

[tibimakai]

Re: Sharp LC-40LE810UN question

DDA002C is not getting Vcc. I don't know how much it should be this voltage.

[tibimakai]

Re: Sharp LC-40LE810UN question

The PS_ON is 3.03V that is normal? You guys are saying that it should be brought up to 5V?
Last time when Olegi told me to try starting manually, I have applied 3.3V to PS_ON. I should try with 5V?

[budm]

Re: Sharp LC-40LE810UN question

That is more than enough to turn on the transistor to turn on an Optoisolator.

[tibimakai]

Re: Sharp LC-40LE810UN question

What do you think that it should be the next step?
The NCP1608 IC(8 pin) "makes" the 400V?
To me it seems that the 400V is not turning on. Everything turns on, then when the code kicks in they are all gone.
Unfortunately I have three TVs that are a pain in the axx to fix. Very soon I will have to take a look again at that shorted LG PS. Without the FETs there is no short(!!).
I still have those two 22" LG and Samsung and that 24" Asus with the burned resistors.
Not looking forward to these repairs.
I will probably bug you guys with these devices. Sorry about that in advance.

[tibimakai]

Re: Sharp LC-40LE810UN question

Can somebody please answer to my question?
Holiday shopping is here and I need some money.