Samsung ln40c630k1fxza

[heavymachines]

Ok i have had this T.V. forever not working. It has been a real royal pain in the arse. I seem to have most difficult time with samsung T.V.'s. So about six months ago i been trying to figure out this sucker and learned much about it along away.


The T.V does have an image and i can see with flashlight no signal dialog so main and assuming power supply is fine. This power supply is a inverter and power supply in one and it uses a balancer board rather than a stand alone inverter.
At one point i did remove the lcd and inspect the cfl's and replaced one due to being pink this set does the 2 seconds to black. the other bulbs do have some black on ends but during those 2 seconds it seems to be white and not pink.

5 volt detect is held low, all other voltages are fine so it certainly a problem either with bulbs or inverter section on power supply or balancer. is this a correct assumption?

Main has been replaced due to broken Hdmi ports and got the improved version with actual heatsink rather than a stone type sink.

Power supply has been replaced long ago as well.

Balancer board i have like 3 of them. Possibly all bad? they were from eBay this was before i banned eBay for buying tv parts.

Now my question is how would i go about possibly forcing the cfl to turn on and stay on, i did try removing the 5v det wire and even feeding it 5 volts no dice.


Yeah this tv has been a fun lil punk lol. But haven't given up on it despite some long breaks in between. I do have a LG 50 inch tv with good leds with broken screen tv works fine other than that i was thinking about converting this samsung to led but i think that would be hard to do. Since the strips length and feeding them voltage would be tricky.

[Davi.p]

Re: Samsung ln40c630k1fxza

Locate the inverter pwm ic, find tv schematic or ic datasheet, for me it's about near all the same story, locate ctimer pin, is possible to do it also without documents, then put it at ground directly or by a 1kohm Res., then switch on and see if lamps stay on (bad lamps), or high volt transf. get hot (them are bad).

[vinceroger69]

Re: Samsung ln40c630k1fxza

not sure if your tv uses this type balancer board but if so maybe good to test it like in this video
https://www.youtube.com/watch?v=Dh01ZepjDp0

[budm]

Re: Samsung ln40c630k1fxza

Can we good clear pictures of what we are dealing with.
DET_5 is the OUTPUT signal generated by the inverter circuit to tell the main board that you have problem with the backligfhts circuit so forcing the DET_5 to fool the main board will not force the backlights circuit to stay on, the backlights circuit is in the protection shutdown already that is why DET_5vV is low.

[heavymachines]

Re: Samsung ln40c630k1fxza

not sure if your tv uses this type balancer board but if so maybe good to test it like in this video
https://www.youtube.com/watch?v=Dh01ZepjDp0

Dude it worked!!! Not exact tv, different mains but everything else is so close i was able to copy the procedure and found out it was the new bulb i put in causing overdraw!!! no wonder why i was stumped on this thing for so long. Anyhow she is up and running, debating disable the bulb or just leave it grounded. it is a new bulb seems to light fine no flickers or anything. You found the exact solution i needed

[heavymachines]

Re: Samsung ln40c630k1fxza

Can we good clear pictures of what we are dealing with.
DET_5 is the OUTPUT signal generated by the inverter circuit to tell the main board that you have problem with the backligfhts circuit so forcing the DET_5 to fool the main board will not force the backlights circuit to stay on, the backlights circuit is in the protection shutdown already that is why DET_5vV is low.

Noted thanks for the info and remember this for next time. Now that the tv is running if you watch the video vince provided should i disable the bulb or just leave the bypass in that fools the detection on balancer.



Yes it is the new bulb, how in hell can it be bad is beyond me, perhaps you will tell me it's not possible lol. The new bulb is slightly skinnier in diameter but same length. I did invest in a caliper to prevent getting wrong diameter bulbs in future but got it after this ordering the bulb with this tv and is the reason i bought a caliper in first place. But could that slight difference be enough to cause an overdraw?

[dick_barton]

Re: Samsung ln40c630k1fxza

Maybe it's not the bulb but the driver transformer itself for that tube or associated ceramic caps. Just a thought.

[heavymachines]

Re: Samsung ln40c630k1fxza

Maybe it's not the bulb but the driver transformer itself for that tube or associated ceramic caps. Just a thought.

Well if it does same thing with other 2 balancers boards i have as well but i'll go ahead and swap and if i need to ground it out again to get it to stay on then that will rule it the bulb right?


What are the chances it is same bad transformer on all three balancer boards in same location?

[dick_barton]

Re: Samsung ln40c630k1fxza

Fair point, highly unlikely. The only other thing I can think of is how secure is the lamp in it's holder.

[budm]

Re: Samsung ln40c630k1fxza

Noted thanks for the info and remember this for next time. Now that the tv is running if you watch the video vince provided should i disable the bulb or just leave the bypass in that fools the detection on balancer.

Yes it is the new bulb, how in hell can it be bad is beyond me, perhaps you will tell me it's not possible lol. The new bulb is slightly skinnier in diameter but same length. I did invest in a caliper to prevent getting wrong diameter bulbs in future but got it after this ordering the bulb with this tv and is the reason i bought a caliper in first place. But could that slight difference be enough to cause an overdraw?

It will take only one lamp to draw too much or too little current to cause the circuit to go out of Balance, so if you do not notice the shadow band on the screen then you can leave it the way it is or you can look further by swapping the lamp around to see if the problem will follow.
NORCAL75 has this Video for this problem since 2012 for Samsung and SONY TV that use Balancer board.
https://www.youtube.com/watch?v=oE6K4xBVweA

[heavymachines]

Re: Samsung ln40c630k1fxza

Thanks i think i'll just leave it way it is there is no dark band as the bulb is still running just fooled the shutdown feedback the bulb is new. Thanks everyone, gonna wrap this up.

[heavymachines]

Re: Samsung ln40c630k1fxza

Ok i wanted to add i feel is important info about this tv. The backlight setting was maxed out!!!! I turned it way down so far she is running strong watched 2 movies on it.

[vinceroger69]

Re: Samsung ln40c630k1fxza

Dude it worked!!! Not exact tv, different mains but everything else is so close i was able to copy the procedure and found out it was the new bulb i put in causing overdraw!!! no wonder why i was stumped on this thing for so long. Anyhow she is up and running, debating disable the bulb or just leave it grounded. it is a new bulb seems to light fine no flickers or anything. You found the exact solution i needed

Glad you managed too fix the tv the main thing is another set saved from the landfill etc i dont bother usually fixing ccfl sets as no one seems to want them in my area so tend too be stuck with them unless i give them away to needy families etc.

[vinceroger69]

Re: Samsung ln40c630k1fxza

It will take only one lamp to draw too much or too little current to cause the circuit to go out of Balance, so if you do not notice the shadow band on the screen then you can leave it the way it is or you can look further by swapping the lamp around to see if the problem will follow.
NORCAL75 has this Video for this problem since 2012 for Samsung and SONY TV that use Balancer board.
https://www.youtube.com/watch?v=oE6K4xBVweA

yes this is the video i was trying too find but found 12voltvids one first, norcal does explain things better/easier too understand in my opinion

[heavymachines]

Re: Samsung ln40c630k1fxza

yes this is the video i was trying too find but found 12voltvids one first, norcal does explain things better/easier too understand in my opinion

Both was useful and got the job done and i learned something , after all a new bulb had me stumped for months!!! But i was able to understand both. I thank you both.


As for tv i try to repair em all regardless of age of set, only ones i don't mess with much anymore is small tv's unless i get it free and free broken monitors i'll fix. So far they all sell, sure some takes time but they do sell. Just sold a 32 inch insignia that had bad caps from around 2004 er 06 can't remember but it sold took me almost 2 months to rid it. it ran fine and had a decent pic and the sound was awesome as it had a built in sound bar. Some i keep for myself.