Medion - MD30140 - Bad Tcon Board

[cholzberger]

Hi,
(Sorry i posted this message to the wrong Section before perhaps an Admin can delete my other post?: https://www.badcaps.net/forum/showthread.php?t=22955)


this is my first post on this great forum, i managed to repair 3 tft monitors just by reading through other posts.

now i have a problem which i can't solve on my own:

I got mysevle a broken Medion MD30140. The Problem with this TV has the following symthoms:

I can turn on the tv, the standby led changes from off to blue, the backlights go on and stay on, the sound is working, but there is no picture displayed.

The Caps all "look good" so i thought the problem may be on the tcon board.
I measured the voltage at the transistors while turned on (relative to chasis-groud):

Transistor: Leg1, Leg2, Leg3
icp1: 0.012, 0.021, 0.21
icp2: 0.27, 0.55, 0.22
icp3: 0.27, 0.55, 0.22
icp4: 0, 0, 0.22

And i measure the following resistance on the legs of the transistors:

Transistor: Leg1-2, Leg1-3, Leg2-3
ICP1: 147,535,476
ICP2: 112,489,447
ICP3: 112,489,447
ICP4: 140,500,472

I guess that the failure has something to do with the missing volts on icp1 and icp4.
Is this what i should dig into deeper? any sugestions where to look further?

I attached a few pictures of the tcon board to this post and hope that the quality is good enough.

tanks on advance for any help.

Edit:
The Voltage on the connection cable is follows (From the left (marked with arrow) to the right):
Pin 0 (Ground): 0
Pin 1: 0
Pin 2: 0
Pin 3: 0
Pin 4: 0
Pin 5: 0.98
Pin 6: 0.73
Pin 7: 0
Pin 8: 0,98
Pin 9: 0.73
Pin 10: 0
Pin 11: 0.96
Pin 12: 0.76
Pin 13: 0
Pin 14: 0.84
Pin 15: 0.88
Pin 16: 0
Pin 17: 0.98
Pin 18: 0.73
Pin 19: 0
Pin 20: 0
Pin 21: 2.96
Pin 22: 0
Pin 23: 0
Pin 24: 0
Pin 25: 0
Pin 26: 5.0
Pin 27: 4,98
Pin 28: 4,98
Pin 29: 4,98
Pin 30: 4,98
Pin 31: 4,99
Pin 32: Ground

[tom66]

Re: Medion - MD30140 - Bad Tcon Board

Near VIN and main connector, there is a device marked "CP". This is a fuse. Check it is not open. I think I worked on the 32" version of that T-con which had just an open fuse.

[cholzberger]

Re: Medion - MD30140 - Bad Tcon Board

Yeah, that fuse is open, thanks,
now i wonder what rating a fuse with a "P" on top has?

is there a table anywhere with this code to ratings conversion?

[budm]

Re: Medion - MD30140 - Bad Tcon Board

May be 1.5A? You should check the resistance between the output side of the fuse and the ground point of the board to see if it has shorted circuits or not. You can use 1 Ohm 1/4W resistor in place for testing until you get the fuse.
http://www.bourns.com/ProductLine.as...lm_chip_fuses]
Just match the foot print.
If you look up the LCD panel spec sheet, it will tell you how much current and voltage the T-CON board and the Inverter board will require.

[cholzberger]

Re: Medion - MD30140 - Bad Tcon Board

Thanks replacing that fuse worked perfectly, monitor is back to life.