Samsung LN37D567F9HXZA wont power on red flashing light

[crushkittykitty]

Background got this tv from a motel, dead red light endless power cycle with no sound.
This is my steps so far.
checked caps appear fine fuses fine checked power coming from power board, stand by power is fine, power on other pins was fluctuating. unplugged cable going to main board back light lights check power levels at plug all fine, (per other posts read here and from powers listed on board, was thinking maybe t-con so plugged back in cable going to main board unplugged lvds cable powered on set back light comes on check fuse on t-con good, plug back in push power button check power to t-con fine at fuse and points at the plug, all showing power if tested when power button is hit before tv turns back off.
is this a sign of a bad t-con board or do you guys think its the main board, or even the power board?
I will post pics of all the boards when the better 1/2 gets home. or if you would like all the readings i can get them as well. The reason I think its the t-con is I read some were that is if the lvds cable is unplugged and the the tv operates then that is a bad t-con I also unplugged the lvds cable from just the main then from from just the t-con no difference.
Its a free tv at this point but I do not want to just throw boards at it till it works. It even came with the box and everthing in it lol minus the remote but I have an extra

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

Unplug the ribbon cables between the T-CON and the LCD panel to see if the TV will power up and the BCKLIGHTS will come on and stay on.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

wow that was fast, thank you for help
unpluging the 2 t-con to lcd no backlight

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

So if you unplug the LVDS then you are able to get the TV to come on and the backlights stay on, is that correct? Most SAMSUNG TVs do not use error signal for the T-CON board to shutdown the TV. What DCV do you have on the T-CON fuse, 12VDC? 5VDC?

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

So if you unplug the LVDS then you are able to get the TV to come on and the backlights stay on, is that correct?

correct and all voltages are fine going to the lvds with cable unplugged

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

so if you have LVDS connected, what DCV do you have on the T-CON fuse?
It does sound like you do have bad T-CON problem.
Do you know the LCD panel model number?

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

with all the cables connected the power fluctuates from 0 to .45 on both sides of the fuse the power is fluctuating all the way back to the power supply.
no idea on the lcd panel number any idea were that number would be located?

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

sorry have to call it a night I will get the lcd panel information after I get the kids off to school

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

Only 0.45vdc may mean that the switched MOSFET on the main board for feeding the B+ to the T-CON board is bad, or the B+ feeding the input side of the switched MOSFET is bad, or too much current draw due to bad circuit on the T-CON board.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

Only 0.45vdc may mean that the switched MOSFET on the main board for feeding the B+ to the T-CON board is bad, or the B+ feeding the input side of the switched MOSFET is bad, or too much current draw due to bad circuit on the T-CON board.

going to start tracing the power back should I be checking this with the t-con unplugged?
I will just do both

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

There should be power pin on the LVDS connector of the main board, this pin should have <1 Ohm between this pin and the T-CON fuse, once you find that then you can check the DCV on that pin of the LVDS on the main board, it does not mean it is OK you do read the correct Voltage that is because it has no load (T-CON) connected, but we can use resistor to simulate the load.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

There should be power pin on the LVDS connector of the main board, this pin should have <1 Ohm between this pin and the T-CON fuse, once you find that then you can check the DCV on that pin of the LVDS on the main board, it does not mean it is OK you do read the correct Voltage that is because it has no load (T-CON) connected, but we can use resistor to simulate the load.

Do you know were I can find a service manual for this or something close. I did a search on elektrotanya and since this t-con is used in other tvs could I just switch out main board with a normal one not the hospitality version. I am sure there is others close I am just scared that once its fixed it will do me no good to use it.
BTW there was more then one pin at <1 Ohm
Here is kinda what I was thinking since it was free, just getting main board and t-con power supply from a broke screen seen some as kits on ebay, the t-con itself is cheap the main board for this I cant seem to find for under 120, power supply is also pretty cheap,
I had to put the tv away till Monday otherwise the kids would use it as a toy.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

Well I think I found part of the issue ic201 has a hole in it.
there is also some discolouration on the back of the main board.
down by the ant plug may or may not be related. so it at least needs a main board or some skill to repair anyone having issue should take pictures then zoom it in that is how I found this. shopjimmy doesnt have the board in stock and it goes back to the fact that this is a hotel tv. So even fixed there is the whole trying to get it to work as a normal tv. any advice I am all ears.
I also have a sharp lc-40e67un with a cracked screen so I will prolly just sell the sony boards to pay for the samsung boards.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

here is the back of the board.
the lcd panel is T370HW03 V.P
will have to see what can be used for a main - t-con - power supply

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

That is switching power supply IC, the output of that circuit feeds the input of the Adjustable LVDO IC205 (1117 series). So the IC may have just failed or the load is shorted so it took out the IC.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

What would you do at this point try and fix the main? If you think it is worth it I will post pictures of the whole board and will try to trace it back. reminds me of the days with old sat receivers. lol I wonder if there isnt a issue in the power supply as well. the t-con I have pictures just havnt went threw them to see if I see anything.

[budm]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

Well at this point you will need to get the P/N as printed on top of that IC to get the data sheet and the pin out so you can do some resistance testing and also need to locate the new IC.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

54327
TI 19A
P2D264
is ic201 on this board

I take it we are going to try and fix. going to pull everything off the power supply and test it again .
Do these reprogram themselves or is it going to have to be programmed?
thanks for the help btw,

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

pin 6 on the power supply looks like has a bad joint or has been hot witch is blue_on
power board with main disconnected (turns on back lights) measured from end of cable. also measured from board.

1. 12.33
2. 4.3
3. 12.33
4. 0 board .63
5. 12.32
6. 7.10 back light flashes
7. 12.32
8. 0
9. 0
10. 0
11. 5.11
12 5.11
13 5.11
14 3.03 back light goes off

all volts are steady,
I know I need at least the one chip but I want to try and get everything I need in one order to avoid the extra shipping.
would it be better to upload these pictures off site I dont want to upload 30 pictures and take up to much space is all.

[crushkittykitty]

Re: Samsung LN37D567F9HXZA wont power on red flashing light

going threw the pictures i came across this one since I have not touched this with a soldering iron I think the main was fixed before.