Zenith model Z27A11S not turing on

[Joust]

i have a TV Zenith model Z27A11S not turing on. i get Nothing.
i suspect the STR53041 - Common failure regulator, but i'm not sure.
any ideas?
anybody have experience with this model?
No voltage at the power button al all. No degause nothing. Fuse is good.
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[David]

ESR check all the capacitors in the power supply. Common problem.
David

 

[Joust]

Thanks David, I will do that.

 

[Joust]

ESR checked caps.
look good AFAIK
or can tell.

can you provide any pointers?

 

[Joust]

really wish i had a schematic...
thanks for the advice.

 

[dkuhajda]

22uf and 100uf in the smps circuit go bad. These take out the regulator,
which in turn takes out the transistor, and the 0.18ohm resistor, plus a
couple of other parts.

After that you need to verify the standby voltages to the system control,
the 9v regulator is another common failure item. Just do standard SMPS
troubleshooting techniques following the schematic.

David

 

[Joust]

I went back and rechecked the 22u and 100u caps with the ESR. they were
very slightly out of spec according to the chart on the front of the ESR
meter. I went ahead and changed them.
The Set turned on on the first attemt.
I reattached the back and then tried it again and nothing.... same
symptom as before.
this is strange....

Obviously the regulators are good.
there is a part that looks like a PTC (thermal activated fuse about an
inch round disk and bright yellow) but is labled as a capacitor. Is it
indeed a capacitor?