Samsung le40a656a1f reaaaaaly slow poer up

[Davi.p]

Re: Samsung le40a656a1f reaaaaaly slow poer up

You are not following any advice, why? Have you tested the power board lonely or not? If it's not ok why are you expecting something works?

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Power supply is ok, I guess there was low voltage when not connected to the rest pcbs. Now (connected) it measures 5v and 12.8v. Anyway I've had it with this set, I think it's time to get rid of it...

[electrocuted]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Hi there, having the same television I get a weird problem. Already recapped the power supply, I can hear sound from the speaker and see backlighting turning on but no image. Looking further, the tcon (input voltage 12.8 Volts so ok) does not have avdd, vgh etc. Left side has no voltage at all. The right side with 3.3V and 1.3V seems ok. Any ideas?

[electrocuted]

Re: Samsung le40a656a1f reaaaaaly slow poer up

The tcon is : 4046FA7M4C6LV0.4

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Unhook ribbons from tcon to panel on tcon side and retest those tcon voltges.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

If those voltages are still missing, maybe test the little mlc caps on the tcon for shorts or abnormal resistance, first isolate tcon by unhooking cable from mainboard to tcon and the ribbon cables from tcon to panel driver boards. That test done with tv unplugged from power.

[Davi.p]

Re: Samsung le40a656a1f reaaaaaly slow poer up

No good to take posses of other one thread..!

[electrocuted]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Unhook ribbons from tcon to panel on tcon side and retest those tcon voltges.

Two panel cables already disconnected, only cable on is the one to main board to get power. The voltage ic I see is TPS65167 and the circuit is something similar to the image uploaded. avdd and vgh are not shorted to ground.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Did you try test in post #66? read carefully, simple test.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

A video is worth a million words, here's one example of tcon troubleshooting there's many many more on youtube, sometimes just buying another tcon is more economical than the time it takes to learn troubleshooting, depends on how much time you want to spend and of course if the tcon is the actual problem: https://www.youtube.com/watch?v=FexX7TGRzDc

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Google results of your board #, you would try to match up the alphanumeric digits on the white box with the barcode on the tcon: https://www.google.com/search?client...M4C6LV0.4#ip=1

[electrocuted]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Thank you for the reply, the tv is not worth buying replacement part. I will try the test you suggest

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

I hear you, it's 15 years old, that being said, I still trust them much more than what samsung has been churning out for the last 7 or 8 years, tcons are usually the cheapest board to replace, have seen them for like 10 dollars or so on ebay sometimes, this model has the Red Rose accent feature and got quite good reviews in 2008: https://www.google.com/search?client...56a1f%2Breview

[electrocuted]

Re: Samsung le40a656a1f reaaaaaly slow poer up

There is no short in the capacitors and diodes. And I can't find a diagram to follow the voltages on the pcb. I will try to see what happens if I connect the cable from the main board to an unused connector!

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Too bad I dumped the one I had, it might be of assistance with the voltages!

[electrocuted]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Yes it could help if it was operational! In the meantime I connected the cable from main board to another plug (the one with the white arrow above CN1) and now it has voltages on the right side as before but voltage has appeared in the input of IC11 (bottom left corner). Nothing else though...

https://www.shopjimmy.com/samsung-lj...4-t-con-board/

[electrocuted]

After many tests the tv won't work! The only one time the screen showed something and the led stopped blinking was this. What should I make of it?

[electrocuted]

No one is familiar with this type of fault, showing this image on screen?

[Davi.p]

i know this set has very consumptive TCON with big heatsinks and fan, the age corrodes the BGA balls and needs to be reballed.. on this type of set only homemade reworking can be accepted.. i think is far too late to do this but try to put tcon on freezer for almost 1 hour, then rapidly mount it and test it, watch if it make improvements or degrades with heat.., check also temperature on the chip on normal mode..

[electrocuted]

Thanks, I'll give it a try and see what happens