Samsung le40a656a1f reaaaaaly slow poer up

[edugimeno]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Ok, I worked on it this evening.
Tried with only one side of Tcon Output. That half was showing good. Tried other half. Good too.
Replaced both flex cables. Now the TV is ALL good. Weird... Waited like 20 minutes and still good. Replaced it at home and after some 45mins of normal use, still good. Should I expect that this is going to fail again later on?
Was it just bad connection at the Tcon outputs? I tried prying all the TV edges close to where all the flex wires are getting into the panel and no effect at all, like there's no bad connection.
Sadly this TV is so old that its tuner doens't work on HD DTV channels but working with an ext SAT tuner it's fine

ALso I wanted to add another question: This TV set has a noisy fan inside, on at all times. This one is noisy. We oiled it with no improvement. Would it be safe to see if it works fine with it unplugged? It's kind of annoying for a living room.

Thanks!!

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Good question, I'm not sure if it would be ok or not, maybe get one of those whisper quiet fans to replace it with.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Arctic P12 are pretty quiet and not too bad of a price: https://www.ebay.com/sch/i.html?_fro...Desc=0&_sop=15

[edugimeno]

Re: Samsung le40a656a1f reaaaaaly slow poer up

The fan itself is not really loud, if I remove if from the panel it's almost silent. But when it gets in contact with the back metal panel, which is like a drum...this small vibration gets like amplified
Im thinking of using some kind of rubber assembly, or even using caulk to attach the fan to the panel so the vibration doesn't reach the metal

[edugimeno]

Re: Samsung le40a656a1f reaaaaaly slow poer up

By the way the other question remained as a mistery.... Is it common that the Tcon-to-panel flex cables have any issue (bad contact, misplaced...) that all this problem gets solved by just unplugging and resitting them? Im asking just to understand if I could be expecting this set to fail again or this solution could be called FIXED

Thanks!

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

If it hasn't acted up again, I'm thinking it was just dirty/loose/oxidized contacts, many tvs have gone to the landfill for just that reason.

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

I just got a set like this (le40a656a1f) with the same symptoms. Plug in socket, red led blinks normally then black screen. Half a minute later led blinks faster and that's all. Background lighting comes up little dimmed little before led starts blinking faster. Disconnected panel ribbons one at a time, the disconnected tcon ribbon but still same! It's the main board I guess, power supply already repaired (bulged caps) some time ago. Anyone still remember what to look for on main board?

[Davi.p]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Have changed all the caps except 400v ones? If not do that..

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

I assume you mean the power supply ones, I'll give it a try.

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Unfortunately same results.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

You said same symptoms, does that mean you have a display on the screen?

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Nothing on screen, although the backlighting is lit dimmed. There must be something wrong with the 13v rail as when load is connected it drops to 4-5 volts and slowly rising to 9-11 volts. The 5v seems rock solid. BTW this is the psu diagram.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

ok, unhook cable from powerboard to mainboard leave it off, I unhook on mainboard side then I trace out the wire from powerboard side, use a 1k ohm resistor to jump from pin1 power on/off to pin 3 stb5.3, then plug into power, then check and see if the 13 volts are there and steady.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

the resistor is used for safety, but if you are very careful, you can just unhook on powerboard side and use a small alligator clip to jump from pin 1 to 3 and check voltages.

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Already done that, power supply is disconnected from the other pcbs and ps on is connected to 5v. 13v pin reads only 9.6v

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

did the backlights come on when you did this?

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

No, the backlight board is unplugged too. When it was plugged, it would light after 10-15 seconds. I could short pins 1 with 5 on the 5pin connector and light it in full.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

.

[kavleas]

Re: Samsung le40a656a1f reaaaaaly slow poer up

Lights right up, voltage still 9.6.

[nomoresonys]

Re: Samsung le40a656a1f reaaaaaly slow poer up

ok, thats a good clue, try heating up the electrolytic caps on the powerboard with a hairdryer for a couple few minutes be sure to get the ones there by the connector, then try the tv, don't wait til it cools down, try tv while it's still hot, also see if those 13's come up while it's still hot.