Zenith TV power goes off

This is usually the power supply. It most likely will need to be replaced.

probably overheating. hoover out the vents and make sure plenty of air can circulate. a case of suck it and see. lol

Hi,

This is an indication of out-of-regulation in the power supply section. The very common caused of this fault is the leaky electrolytic capacitor in that section. It will drop the supply from normal voltage and will disable the unit.It needs a little warm-up to make itself stable but the symptom will get worst. Sometimes it has a bulged/dome at the top but not all, it is better that you have a capacitor checker/tester to determine its condition. Your unit will back to normal again if the leaky capacitor is isolated. Yes fixing the power supply is quite technical but in this case a little backround in electronics will be fine because electrolytic capacitor is the only parts that are going to be replace. If you don

Capacitors can be deformed or some solderings on active components can be bad.
Amplitude change and image geometry want change when warming up, buy a canister cold spray and spray some components, Be careful when working at high voltages in the fly-back (horizontal) circuit by crt television, and tripler and Focusing voltage.

Hi, Replace the bulging capasitors on the main power supply board. Thanks.

I sorry to say I think you have a component failing that is related to heat. 15 years is a long time and if the TV was used in hpot conditions over the years it may well be the proble, or it's just old.

The effect you described sounds a lot like a failed solder joint.

There are points on the circuit board that are subjected to heating and cooling each time the set is powered up, then down.
The solder joints near these areas can fail from metal fatigue as will any metal that is forced to expand and contract repeatedly.
These fractures are minute and can often only be seen under magnification.
Once found, they are simple to fix; removal of the old solder and resoldering will restore electrical contact in seconds.

If you can find a gray-haired tech nearby who is retired, maybe early since repair is a business stagnated by cheap labor in Asia, he/she will know where these areas are and can robably get rid of your lottery-like operation.
Or, if you have way too much time on your hands and are willing to buy a decent soldering iron and dig into the guts of your set, you can probably find the problem yourself.

While semiconductors do fail (sometimes for the same reason), since the set does sometimes restore itself, it isn't likely that any of those has died.

I would be torn to toss the set if it is otherwise OK for the simple reason that if repaired, it may outlast 80% of those bought in the last 2 years.
It is amazing the number of problems that are happening on new, sophisticated sets and it is traceable to lousy quality in parts and assembly.
I have one LCD set I will probably junk this year that is only 2 years old, flawed when I bought it new, and has a failure producing a vertical black stripe that would require replacment of the $4-500 panel.
Junk - Specifically, WALMART junk.

Comment by Guest, posted on Oct 25, 2008My Aquos has the same problem. I'm not sure how I discovered this, but when I lean the TV forward and hit the power button it will turn on every time. If the screen blacks out and I don't lean it forward when I hit the power button, the screen will just remain blank. It is very weird, but at least repeatable.

- Thank you, Guest. That did it. It definitely seems to be a problem with the TV. Tilting it and hitting the power button helped me get the video back.

Hi Pswglaw,

From the way you describe the problem, it seems you have a high voltage leak. To check this, make the room dark and look into the back of the TV while turning it on. If you see something like lighting jumping around you have this high voltage problem. The TV will eventually destroy itself under this condition. I would suggest not using it until you get it repaired. The repair cost will be much lower if the TV is still working when you take it in. The high voltage leak will destroy more parts and cause the TV to stop working. Then it will blow a fuse.

MyTvGuy

When TV does not start, and sometimes you hear a clicking noise, that means that the TV is on protect mode.

Try first leaving the TV power cord unplugged for some times, let say one hour or so.

Also ensure that the fault is not coming from a faulty receiver box sending bad signal, check if you get same problem with no receiver box or dvd connected.

If that does not work, and you keep having a flashing led on front of the TV, and tv turning off by itself after a while, that indicates a fault condition.

The flashing light indicates a diagnostic state called protection.
When the TV goes on protection there are only two possible reasons.

1The internal circuits are jammed because of electrostatic charges accumulating on capacitors, or because of a wrong voltage read by the main chip on your monitor controller board. this started the protection circuit.

2 The protection circuit detected a wrong voltage or abroken contact, identified an internal fault and kicked in , startingthe flashing light.


If you are in situation one, then theTV will reset just unplugging power cord for one or two hours,sometimes even minutes.

If you are in situation 2 , then there is an internal fault.

Common faults that can occur are a blown capacitor on power board, a convergence IC has blown, or a fault on Digital board.

Check also the video cable or any external connection cable, if the cable is shorting, or the connector is bad, you can get same flashing state because of the video cable.


If under warranty contact the manufacturer ringing the number on the user manual

If you want to repair at your own expenses, just locate any good qualified repairer.