Sharp LC48LE551U

[simcole]

Hello everyone. Long time reader, but I think this is my first repair question. I've fixed about 12-14 TV's so far thanks to these forums as a hobby. So I have a weird main power board for a Sharp that I need some advice on.

The TV does not show any standby voltage when it's plugged in. This board has some weird names for the power connector that I don't know what it means (blu_on).

Anyway plugged in and off here are my voltages on the power board:
Pin 10 - Dim2 - 0v
Pin 9 - Dim1 - 0v
Pin 8 - Blu_on - 0v
Pin 7 - PS on - 0v
Pin 6 - ground
Pin 5 - ground
Pin 4 - ground
Pin 3 - 19v - 18.6
Pin 2 - 19v - 18.6
Pin 1 - 19v - 18.6

I'm GUESSING Blu_on is my 5v? What's that stand for?

Here is a picture.

What do I test now? I haven't been able to locate the service manual yet. Thanks in advance for all your help.

[budm]

Re: Sharp LC48LE551U

BLU = Backlights ON.
This LED Backlights TV may use 19V STBY.
Can we see the whole backside of the TV so we can see how all the boards are connected together?
Also need clearer pictures that are in focus.

[simcole]

Re: Sharp LC48LE551U

Here is a photo. I'm trying to get this thing in focus. I need to wait until daylight to get some better lighting. If this used 19v standby then maybe the main is bad somewhere.

[tom66]

Re: Sharp LC48LE551U

Sigh, another example of the "clone wars"; a Sharp branded TV that's not made by Sharp, but the lowest bidder in China.

[simcole]

Re: Sharp LC48LE551U

Does that mean nobody can help? I could really use a little guidance as searching here for a similar design has turned up nothing and since I can't find the service manual.

[budm]

Re: Sharp LC48LE551U

Right now it points to the problem on the main board, it is not sending command signals to turn on the main power supply.
You can try and see if the main board has any fuses, 3-PIN Voltage regulators C that need to be check, also try disconnecting the cable to the T-CON board and see what happen.

[simcole]

Re: Sharp LC48LE551U

Right now it points to the problem on the main board, it is not sending command signals to turn on the main power supply.
You can try and see if the main board has any fuses, 3-PIN Voltage regulators C that need to be check, also try disconnecting the cable to the T-CON board and see what happen.

Wow, thank you for the response. I though I was on my own. Anyway, there are no fuses or 3pin VR's on it. I disconnected the T-Con and nothing happened. I checked voltages on P_ON and BLU_ON while pressing power, nothing happened. I suppose it might be time to buy a new board, but I wish there were something else to check first. Any last ideas anyone?

[nomoresonys]

Re: Sharp LC48LE551U

like Budm says, sure looks like a mainboard issue, they can be a bear to trace down to component, a new board is probably the way to go.