Samsung LN46C610N1F no backlight

[Danstona]

Re: Samsung LN46C610N1F no backlight

Ok, so I am seeing -14.87vdc on what I believe is the VCC leg. Tracing it on the board it connects to CP818

[budm]

Re: Samsung LN46C610N1F no backlight

You mean +14.87VDC if you use the negative leg of the main filter cap as the GND REF. for the meter.
If it is then that IC is not working because it has VCC but it is not running.

[Danstona]

Re: Samsung LN46C610N1F no backlight

You mean +14.87VDC if you use the negative leg of the main filter cap as the GND REF. for the meter.
If it is then that IC is not working because it has VCC but it is not running.

Ok, I put negative lead to tv chassis and positive to VCC, my Fluke meter read -14.87. I don't feel comfortable crossing sides with the meter leads when the board is lifted and loose.
If this IC is bad, before I go replacing it and CP820.. could there still potentially be other problems? I don't want to end up rebuilding the entire PSU if a working replacement is available. I'm also playing around with a 50" LG that I need to open, and see what parts may be required while ordering.

[budm]

Re: Samsung LN46C610N1F no backlight

You are working in the hot side of the circuit so you cannot use chassis as the GND ref. for your meter, the Negative leg is the GND ref. for the meter, that is why it should not be negative Voltage as your report.
At this point you may be better off buying a working replacement board.
Do you have tools to do surface mounted repair works?

[Danstona]

Re: Samsung LN46C610N1F no backlight

I do not and have not ever attempted surface mount repair work. I just have a regular adjustable temperature iron. If we're fairly certain that the PSU is the issue, then I'll order up a replacement since I cannot properly fix.

[Danstona]

Re: Samsung LN46C610N1F no backlight

On second thought, what would be the best preferred tools to properly repair this? Shopjimmy doesn't say its not available, but when you click on it its out of stock... I'd really like to salvage the set rather than toss it.
Basically looking for suggestions of soldering iron etc.

[budm]

Re: Samsung LN46C610N1F no backlight

I do not and have not ever attempted surface mount repair work. I just have a regular adjustable temperature iron. If we're fairly certain that the PSU is the issue, then I'll order up a replacement since I cannot properly fix.

At this point we know that we have PS-ON but the PFC circuit did not operate so without boosted Voltage then you will not have the backlights.
We do not know the condition of the main board and the T-CON board unless you can see the image on the screen using the flash lights.
You will have to practice on some junk board first before attempting on the real board otherwise you can damage the traces.

[Danstona]

Re: Samsung LN46C610N1F no backlight

I can do that. I just need advice on the best iron to buy. The picture is there with flashlight. So input board and tcon seem to be operating.

[vinceroger69]

Re: Samsung LN46C610N1F no backlight

shopjimmy do a repair kit for this board
https://www.ebay.com/itm/Samsung-BN4...-/361606113610

[Danstona]

Re: Samsung LN46C610N1F no backlight

shopjimmy do a repair kit for this board
https://www.ebay.com/itm/Samsung-BN4...-/361606113610

thanks but no parts in this kit are of the defective ones

[budm]

Re: Samsung LN46C610N1F no backlight

The kit is for xxx340B, your board is xxx341B.

[vinceroger69]

Re: Samsung LN46C610N1F no backlight

The kit is for xxx340B, your board is xxx341B.

sorry op not sure why in my search that wrong board number came up.

[Danstona]

Re: Samsung LN46C610N1F no backlight

budm, how do I go about finding that IC on digikey to order, like value. Along with the CP820.. and maybe get that CI818 just incase for future.

[budm]

Re: Samsung LN46C610N1F no backlight

The schematic gives you the P/N of the IC and the value of the cap.

[Danstona]

Re: Samsung LN46C610N1F no backlight

I did a search for the fan7530 they come up with an MX at the end, is that compatible thats my only concern...

[yshraybm]

Re: Samsung LN46C610N1F no backlight

Did you ever figured it out? I too have blown CP820. Was it just capacitor or was it more to it?

[nomoresonys]

Re: Samsung LN46C610N1F no backlight

throw a new one in there and try it.