Goodmans GTVL28W26HD - TV stuck in standby

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Ever so slightly from 0.0 to 0.3

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

That is odd -- seems like some part of the main board is turning on the PS ON (CT) signal but it's too weak, could be there is a short on the power board which is holding down PS ON. Try with a 100 ohm resistor to 5V (other end to CT), does it rise to at least 2V?

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Try with a 100 ohm resistor to 5V (other end to CT), does it rise to at least 2V?

Sorry, I don't follow what you want me to do.


As is, the CT is showing 0.5v at both the power side and main board.


The multimeter is showing a 0.01 - 0.02 reading with just the ground wire on the TV chassis.

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Unplug connector from main board end, connect a 100 ohm resistor between the 5V which is working and the CT pin, then measure the CT pin, is it more than 2V?

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Ok Thanks Tom, much appreciated, It will be a day or two before I reply.

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Hi Tom, budm,

I have got some 100R resistors.

On which board am I to connect it?
From which pin to which pin?

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Unplug the power connector from the main board side, then use the 100 ohm resistor to connect between the 5V and CT pins, I'm not sure on numbers but they should be labelled.

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

There is no 5v pin labelled

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

My error I mean 12V.

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

CT pin then measures 12.3v

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Does 24V etc come on?

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Yes Tom, the 24v pins are showing readings of 24.1

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

OK this definitively indicates a main board problem.
You can try checking voltage regulators https://www.badcaps.net/forum/showthread.php?t=22231
Other than that, the only option may be to replace the main board, unless detailed schematics of it are available.

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Ok, Thanks for help so far.

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

Main Board is BEKO XLA190r-5
(pic attched)


I can see three voltage regulators:

IC302
17-33G
RB738
Pin 1 ___ 0.00
Pin 2 ___ 3.29
Pin 3 ___ 5.23


IC304
78M05
RF739
Pin 1 ___ 0.12
Pin 2 ___ 0.00
Pin 3 ___ 0.44


IC305
1587M
RB738
Pin 1 ___ 0.58
Pin 2 ___ 1.83
Pin 3 ___ 5.15

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

All regulators look in tolerance. Reg #2 is not powered. Can you get a picture of the main board so I can see what DC-DC devices there are?

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

I just put attachment on previous post.
Do you want close-up of any particular area ?

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

attachment

[tom66]

Re: Goodmans GTVL28W26HD - TV stuck in standby

I see only one DC-DC there, small black device bottom middle of board marked "100". What voltage do you see on each end?

[Declan_Ireland]

Re: Goodmans GTVL28W26HD - TV stuck in standby

5.23v
5.32v