Servive Manual Needed

[shorteddiode]

Westinghouse VK 40F580D or any model or any other model that has the same boards. I am looking for voltages for the voltage regulators on the main board.
Thanks everyone

[tom66]

Re: Servive Manual Needed

They are usually written on each regulator, or in case they are adjustable, they should have 1.25V between ADJ and OUT.

Part #s of the boards and I may have a schematic.

[shorteddiode]

Re: Servive Manual Needed

Here are photos of the boards in the TV,
the power board number is F693006680
Main Board 5097695303
Inverter 1400H1-20A

I am not getting any back lights, The power board is putting out the voltages that are required on the silk screen. I tested the primary side of all the transformers on the inverter board and they all test good. Just for giggles I installed a known good power board and it made no difference. I have not checked the T-Con, will a bad T-Con prevent the back lights from working???
I have not hooked it up to a signal to check for sound, Just thought of that.

[shorteddiode]

Re: Servive Manual Needed

I dug farther and need some help, I have no back lights, no sound and using a light against the screen I see no video. I am not getting voltage to the T-Con checking it on both sides of the T-Con fuse.
On the power supply plug on the bottom of the board the voltages are
24V
24V
24V
BL-ON 5.19V
PWM 3.3V
5V
5V
PS-ON 5.18V

The plug on the left side
VCC 12V
FBK 0V
LD 12V

I checked the voltage at each transformer on the inverter board as the set was turned on. Non of them exceeded 1.9volts but quickly went down to 0 but all the voltages out of the power supply stated the same.
On the main board
U31 5V
Q90 5V
Q91 5V from center pins
Q92 5V

U48 Pin1 2.0V, pin2 3.3V pin3 5.2V
U49 pin1 .56V, pin2 1.8V pin3 3.3V

I scoped the connector to the T-Con and the photo shows the display I received on all pins The scope was set to Time/Div 05 and Volt/Div .005

[budm]

Re: Servive Manual Needed

That power supply board is the combo inverter/power supply board, the two wires (PINK, WHITE) on the top left of the board is the high voltage output connector which feed the Backlights balancer board, each one of those little transformers on the Balancer board are current sensing transformer for each lamp, if the lamp draws to much current, the FBK pin will go high to trigger the inverter circuit to go into shutdown mode, it works the same as SONY/SAMSUNG design.
You can ground FBK pin to ground using 100 Ohms resistor to see if the lamps will at least flash for seconds, you may want to look at them in the dark room.
Can we see good pictures of the bottom side of the Inverter/power supply?
You can make something like this for testing to see if the high voltage transformer is putting any high voltage pulse at all; Just touch that probe to one of the Pink/white connector one at a time.
http://s807.photobucket.com/user/bud...tml?sort=3&o=0
http://s807.photobucket.com/user/bud...tml?sort=3&o=1