RCA TV no picture, replaced all boards. Backlight ok

[budm]

Re: RCA TV no picture, replaced all boards. Backlight ok

"I checked the voltage at the main board with and without the LVDS cable connected. There was not 12v anywhere. (The highest was about 2.3v) The cable is not damaged or pinched."
You have to have the switched 12VDC (It will be present when the power supply board receives the PS-ON from the main board) from the power supply board to feed the main board, then that 12V is fed through the switched Power MOSFET to supply the 12V to the T-CON when TV is powered on. The 12V is also used by the Audio circuit.
You should also report the DCV reading of each pins of the connectors of the power supply to see what you have and what you do not have.
Also post closed up pictures of this MEGMEET MLT-198TX power supply connector without the cable in place so we can see the labels of the connectors' pin.

http://www.shopjimmy.com/megmeet-mlt...wer-supply.htm

[Bfritz97]

Re: RCA TV no picture, replaced all boards. Backlight ok

From top to bottom (bottom being where CON5 is printed):
12.25
12.25
-0.02
-0.02
-0.02
5.08
5.08
5.1
4.23
5.08
5.08
-0.03
-0.03
This is on the main power board at the main connector. It is the only connector that has voltages printed next to it

[budm]

Re: RCA TV no picture, replaced all boards. Backlight ok

You correct Voltages (Standby 5VSB, switched 5V, switched 12V, and STB (PS-ON) signal).

[Bfritz97]

Re: RCA TV no picture, replaced all boards. Backlight ok

So does this mean that the power supply is ok? And the main board is telling it to turn on, but could something else be wrong on the main board?

[Bfritz97]

Re: RCA TV no picture, replaced all boards. Backlight ok

Hello?

[budm]

Re: RCA TV no picture, replaced all boards. Backlight ok

""I checked the voltage at the main board with and without the LVDS cable connected. There was not 12v anywhere. (The highest was about 2.3v) The cable is not damaged or pinched." Since you do have 12V at the power supply, then you should have 12V at the connector of the main board. If you do have it at the connector then you have problem on the main board somewhere.