Toshiba 50L3400u. Tv. Screen flashed on the goes off.

[Familyman0409]

I can shine a light in the screen and see image. Also have sound. Replaced led strip. Still no change.

Led board is built on to ps unit. Using a multimeter. Checking on the out terminals for the led. There are 8 wires. 4 red 4 black. With red on red and black on black with the meter I get no reading. When grounding the negative if meter to frame I get 40 volts. Ps says it should be 52 volts. It's like the ps is not grounded.

Thinking power supply?

Any ideas?

[budm]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

We need good clear pictures of the whole back side of the TV showing all the boards and good clear straight shot pictures of the whole top and bottom side of the power supply board to get any help.

[Familyman0409]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

sorry. my phone wouldnt upload them. here they are.

[budm]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

OK:
You will leave the black probe on the chassis, Red probe on any one of the LED + then turn on the TV while keeping an eye on the meter to see how high the Voltage jumps up to and settle down to 40VDC. Report the reading then we can go on to the next step.
Your TV has 4 sets of LED strings with 4 sets of LED drivers.

Your power supply board:
PK101W0350I (FSP107-3FS03)
http://www.shopjimmy.com/toshiba-750...led-board.htm#
Pictures provided by shopjimmy.

[Familyman0409]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

It jumpsto 69. Volts on all 4 leads. Then settles around 40.

[budm]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

It jumpsto 69. Volts on all 4 leads. Then settles around 40.

OK, the boost converter is OK but it is not seeing the load so it goes up to 69V (instead of 55V with loads) and then shutdown. We need to get the P/N of the LED driver IC U901 next.

[Familyman0409]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

So it needs the led driver ic?

[budm]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

We need to get the P/N of the IC so we can look at the spec sheet and find out if it has the correct Voltages for the IC to run or not first.

[Familyman0409]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

Alright. where should i get the part number from?

[budm]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

It is printed right on top of the IC which is covered by the heatsink right now.

[Familyman0409]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

OZ9998HDN
thats the number on it

[budm]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

Not much info out there.
We did not have much luck on this thread either:
https://www.badcaps.net/forum/showth...ight=OZ9998HDN

[Familyman0409]

That stinks. So you think I should go with a power supply? Or something for else.?

[Familyman0409]

Re: Toshiba 50L3400u. Tv. Screen flashed on the goes off.

ordered a new power supply. installed and the tv came up and is working fine.