Sanyo DP42849 - Backlight Not Turning On

[budm]

Re: Sanyo DP42849 - Backlight Not Turning On

The resistance can be anything from 330~1000 Ohms, it is for limiting the current in case you have mishap and connect it to the wrong place like grounding the 5VSTBY to ground.

[coreyand]

Re: Sanyo DP42849 - Backlight Not Turning On

Understood, I found a few resistors on an old amplifier board I have been robbing parts from for a while, the two I found read 9.75k ohms. That should work, give me a minute to de-solder them from the board and put them in those places on the psu of the sanyo.

[budm]

Re: Sanyo DP42849 - Backlight Not Turning On

BTW "I suspect something is wrong with the main board. Doesnt the 3v for the BL_On come from the main board? Also when I jump that wire from the standby to the bl_on there is nothing on the screen and it is completely blank," So you are able to force on the backlights but with all the cables connected you still do not see pictures? or the backlights are still not on? 9.75 K (9750 Ohms will be too high).
Brown, Black, Red = 1000 Ohms, 4th band should be Gold for 5%.

[coreyand]

Re: Sanyo DP42849 - Backlight Not Turning On

Wait 9.75k ohms would be nearly 10,000 ohms wouldnt it. Ill see if I can find a better substitute.

[coreyand]

Re: Sanyo DP42849 - Backlight Not Turning On

I can force the backlight on by putting a jumper wire from the 5v stby to the bl_on, however the backlight only stays on second or 2 if that. And yes all cables connected.

[coreyand]

Re: Sanyo DP42849 - Backlight Not Turning On

Okay, I put the resistors I found between the 5v stby and the ps_on, and the other 5v stby on BL_on. The backlight remains on with everything else unplugged from the PSU. I guess this would mean that it is for sure the mainboard or the main IC on it.

Also I plugged the cord back into the main board with the resistor in place for the bl_on to the standby to force a backlight and I when I turn on the tv I get the back light and nothing else. In addition I get 5v on the ps_on on but .022mv on the Bl_on. So a new mainboard I suppose?

Any suggestions?

Thanks for your help once again all.

[coreyand]

Re: Sanyo DP42849 - Backlight Not Turning On

Oh and all other voltages on the board look good. 12v ect.

[budm]

Re: Sanyo DP42849 - Backlight Not Turning On

If you have every hooked back up and able to get the light source to stay on then if the main board is OK then you should see the pictures on the screen, if not then the main board is not working.

[coreyand]

Re: Sanyo DP42849 - Backlight Not Turning On

If you have every hooked back up and able to get the light source to stay on then if the main board is OK then you should see the pictures on the screen, if not then the main board is not working.

I believe your right bud. I have the main board plugged in with the jumper resistor to the bl_on and have back light but just blank, looks like I need to order a main board. I cant believe the main board for this sanyo is $150 + shipping used. Pretty high just for that but I guess if it gets it working.

[budm]

Re: Sanyo DP42849 - Backlight Not Turning On

I would not spend $150 on SANYO TV.

[CapLeaker]

Re: Sanyo DP42849 - Backlight Not Turning On

pricey main board for that TV. Ouch!