Sharp LC46d85u struck by lighting

[Landcaster3]

Hey Guys I have a sharp TV LC-46d85U, It was struck by lighting and these are the current symptoms.

1. Flash two power and OSD light 2x then single OSD light afterwards.
2. Was able to get into service mode and reset the monitor faults
3. Upgraded the firmware
4. The TV starts and works for an hour, sound picture etc.
5. The TV looses picture, still hear the speakers, with no flashing lights solid OPS and Power lights, the TV becomes unresponsive and the only way to shut it off is by holding the side power button for 5 seconds

T/S steps so far

1. New used power board
2. New firmware
3. Tried two new used main board, but could never get them to reset and show me the service mode...backlight came on, solid green but never any picture
* They came from a different TV the Part Number was the same including sticker but now sure it was the same software
4. I'm able to cold spray one of the memory chips on the main board and the tv will start right up, was not able to do that with the new boards


At this point I don't know what it is... I think is a main board but I just cant rule out the panel/ inverter boards any help would be greatly appreciated

[dick_barton]

Re: Sharp LC46d85u struck by lighting

Will it start immediately every time you cold spray the memory chip and if so what part number is the chip?

[Landcaster3]

Re: Sharp LC46d85u struck by lighting

the part number for the chip is IC8151, yes it will start every time but will shut down right after it gets to normal temperature. That's the reason I put two new (used) main boards..

[Th3_uN1Qu3]

Re: Sharp LC46d85u struck by lighting

What i would do is get a flash memory reader/programmer, desolder the affected memory chip from the original mainboard, freeze spray it to make sure the right data comes out, read it to the computer, then buy a new chip and write its contents to that. That should fix it.

Then put the other two boards back on ebay.

[dick_barton]

Re: Sharp LC46d85u struck by lighting

the part number for the chip is IC8151, yes it will start every time but will shut down right after it gets to normal temperature. That's the reason I put two new (used) main boards..

Is that the number printed on top of the IC?

[Landcaster3]

Re: Sharp LC46d85u struck by lighting

Thanks but what you are saying is that my main board is bad...that's not really helping me at all...what I need to know for sure is what that chip does...is it in charge of self diagnostics of the monitor itself. I don't know that's why I started this thread...

Couple of points I like to make are desoldering this chip is beyond my skill set they are just too small.
Buying a chip writer and reader wont be economical
Assuming that the chip is bad and that I need to replace it just brings me back to the same problem I had ...Please I need to know what if any are the different version of the main board...why one works for an hour and the others don't even give me any picture after the reset.

[Landcaster3]

Re: Sharp LC46d85u struck by lighting

The number printed on the chip is Hynix 827A (HY5DU561622FTP-D43)...The service manual calls them as follows 256-Mbit ( 16M X 16bit) DDR synchronous DRAM...so I guess the OS of the TV is store there somehow affecting the power on start diagnostics...any ideas fellows.

[Landcaster3]

Re: Sharp LC46d85u struck by lighting

Hey guys got an update, I thought my CPU was getting too hot and since the system is freezing on me with no codes I thought of putting a fan and leaving it one for a while...I did that last night and the temperature was really cool but still got up this morning, I had sound but no picture and no response from the tv. Could this be the inverters some please help me out ...

[Landcaster3]

Re: Sharp LC46d85u struck by lighting

Update I did some experiments seeing if the temperature was causing my problem but so far I have not been able to confirm that it was...The TV still shuts down after an hour and I have no faults ... I have however found out that I'm loosing a 3v Error wire when the TV is fail mode. I have also attached a schematic of my TV...I know people like to see picture...let me know what else I must do to get some help. I really need it on this TV.

[Landcaster3]

Re: Sharp LC46d85u struck by lighting

Update, have not been getting any help from the forum maybe because not many people have the sharps...In any case I will continue to document here what I'm learning so that someone else can skip some of my t/s steps...

I notice my Error 3 volt wire coming from the TCOM or at least the ground is going to 0 volts when my screen goes blank. So I disconnected the connection to the panel and left the TV on over night...taking the panel out of the equation I manage to get the TV to fail, sound still worked so I know my main board is good leaving only the TCOM board ..will change it next will keep my thread going until I find the problem.