RCA LED46C45RQ,Sound but no Back lights

[tennno`]

Sound no picture RCA LED46C45RQ,Power Supply Board RE46HQ1301.
Has All voltages coming from main board.No voltage going to
Back lights from power board.Have no Schematic.Back lights work when
Led Back light Strip tester is used.Tester shows 110 volts from each
side.Also if you use the side controls and use the vol +or- tv shuts
down.
Thanks for any help

[dskall]

Re: Sound but no Back lights

You have 0v at led connector when you power on?

[neilc6]

Re: Sound but no Back lights

Your LED tester may not detect the bad LEDs since it runs at much lower current than the TV.

Every RCA LED TV I've encountered had bad backlights if it turned on with no backlight or flash of backlights. Impossible to get new LED strips for them so I repair the individual LEDs and turn down the backlight level as low as possible in the service menu. Menu-1-1-4-7 or source-2-5-8-0 under panel settings. I've encountered models where lowering the backlight didn't save or I couldn't adjust it with the remote cursor buttons. Some do have energy savings picture mode which run the backlight a little lower than max.

[tennno`]

Re: Sound but no Back lights

Yes 0 volts

[tennno`]

Re: Sound but no Back lights

When tester is put on back lights ,It lights in full Brightness-no dark spots. Picture Perfect

[dskall]

Re: Sound but no Back lights

So power board is bad. Need to check components in led circuit.

[tennno`]

Re: Sound but no Back lights

I can't find a LED46C45RQ Schematic (RCA)

Supply Board RE46HQ1301

[dskall]

Re: RCA LED46C45RQ,Sound but no Back lights

Need good pictures of boards.

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

Hope this helps

[dskall]

Re: RCA LED46C45RQ,Sound but no Back lights

And you are getting your BL_ON voltage? Need to check ds2 and ds2a for shorts. Also need one good picture of whole back of board.
https://www.shopjimmy.com/rca-re46hq...ply-led-board/

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

Took ds 2 and ds 2a out of circuit , checked good also Qs7&9

[R_J]

Re: RCA LED46C45RQ,Sound but no Back lights

Sound no picture RCA LED46C45RQ,Power Supply Board RE46HQ1301.
Has All voltages coming from main board.No voltage going to
Back lights from power board.Have no Schematic.Back lights work when
Led Back light Strip tester is used.Tester shows 110 volts from each
side.Also if you use the side controls and use the vol +or- tv shuts
down.
Thanks for any help

So you have the BL_ON voltage for sure?

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

FYI Just got new board installed it and the same thing happening

[R_J]

Re: RCA LED46C45RQ,Sound but no Back lights

FYI Just got new board installed it and the same thing happening

Which board? Power supply? Main?

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

Power supply

[R_J]

Re: RCA LED46C45RQ,Sound but no Back lights

I suspect you are not getting the BL-ON voltage from the main board to turn on the back light circuit

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

Also I noticed that when tv starts up I get voltage at connector going to back light and then the voltage drops off (new board)

[R_J]

Re: RCA LED46C45RQ,Sound but no Back lights

Also I noticed that when tv starts up I get voltage at connector going to back light and then the voltage drops off (new board)

What does the BL-ON voltage do on CON4 when the tv is first turned on? does it stay the same level when the backlights are on and then turn off?

You likely have a bad led in the panel. one bad led will trigger the backlight protection circuit to shut down.

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

got 5 v sb rest dead turn on tv got all voltage that are supposed to be there 12v 5v etc.

[tennno`]

Re: RCA LED46C45RQ,Sound but no Back lights

Will tear it apart and see.