LCD TV 26 Stay in Standby mode Red led

[flosers]

Hello,
I have a problem with my LCD TV 26" "VD TECH TQT26AVD.She stay in standby.
All capacitor seem to be good, I have checked the output of the PSU board and all voltage are good just the last "the standby connector" have 3,78v I ‘don't know if it is good or not?
In some LCD it is the EEPROM component who need to be change but I haven't this component...
Thanks in advance
(Sorry for my English, I'm French)

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

Oh No ! you say its him again. Well only a small thing - TQT26AVD doesnt come up on google - that rarely happens are you sure the number is correct

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

Sorry I don't undersand? Yes it is the right number but it is a low cost TV so maybe it's because its a rare tv?

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

Ok -it is still usual to get some sort of "Hit"
As there is nothing you will need to to post pictures of the back of the set
showing the generl layout then pictures of the individual boards and also give the board numbers - they may come up on a search.
Try and find a small 50v cap on the Primary HOT side of the power supply
and CAREFULLY test the voltage on it do not touch any other componnents or heatsinks in that area.
I have to go make dinner now so catch up later.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

Good diner!
I test it, I have a inexact value between 0 and 3v in AC mode.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

Good diner!
I test it, I have a inexact value between 0 and 3v in AC mode.

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

Ah! teo dinners and you have tested it twice
Meter should be on DC to test voltage on a cap.
Got me there - dont think I have heard of those boards either.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

Ok sorry, now I have 256V.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

I would like to test the PSU board without the logic board with a 3v battery but the psu board don't have on/off pin... Have you any sugestion?

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

Ok sorry, now I have 256V.

No you havent - at least not on a 50v cap!!

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

I have check again I have! I have 320v (check 4 time)

[stj]

Re: LCD TV 26 Stay in Standby mode Red led

possible,
if it's a startup cap then it's charged through a resistor from the rectified mains.

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

possible,
if it's a startup cap then it's charged through a resistor from the rectified mains.

What 300V on a 5Ov cap???

@Floser

Which cap are you testing -Its not a blue one so that leaves 3 C2F C25F or C20F

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

It's the big one Horysontal.The C1 have 24V (at the right of the big caps),13,6V for the C2F

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

Yes I thought so - that hardly fits the description small 50v cap!!

Its the biggest cap in the machine and is probably 400v or 450v.

I cant see if either of the other 2 are 50v so you must tell me.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

C2f and c25f are 50v capacitor and the C1 is a 35v

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

Ok one or both of the 50v caps are start up caps - if you can get to them it would be useful to know what voltage they are at on standby and what if anything changes when you press the on button. Another idea I just seen mentioned on another thread is to pre heat those two caps with a hairdrier for a minute or two before switching on.
I am still thinking about jump starting. There seems to be more cables than usual and I cant see all the pin details - example what is on the two pins next to 24v? What is that
cable with just 2 wires - perhaps pictures of each connector would help and also look
on the back to see if any more descriptions.
Do you get any voltage on the 24v pins?
Probably a tomorrow job now as I guess its midnight there.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

The tv is On! But I'm afraid that if I shut off the tv she don't start after.

[flosers]

Re: LCD TV 26 Stay in Standby mode Red led

24v pin are good, 24v on It.The TV after some restart still on but I have tried to do the test on 50v caps but I did a short circuit .
So tomorow I change the fuse and I will continue the test.
Thanks for you help,I appreciate

[selldoor]

Re: LCD TV 26 Stay in Standby mode Red led

The tv is On! But I'm afraid that if I shut off the tv she don't start after.

Unfortunately you cant keep it on for ever - but its always nice to see it might
work eventually.

Hopefully it is just a popped fuse - I did say "CAREFULLY test the voltage on it do not touch any other components or heatsinks in that area"

It is looking like a loose connection/bad solder joint so pictures of the backs of the boards may help us spot something.