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First time here, but thought someone might have a clue. Almost every night, for the past couple of months, my Sharp TV goes dark, off goes the pilot light. Never happens more than once a night. I'm not doing anything but watching the picture, remote control just sitting there. I can easily fix it by using the remote to turn the TV back on, but it is clearly an anomaly that doesn't seem to be going away. The ultimate intermittent problem -- I haven't found a way to induce it. The cable box and Denon receiver stay on and are unaffected,
I'd be grateful for any thoughts.
Follow Ups:
The first return on a DuckDuckGo query of "sharp aquos auto turn off'.
"Why does my AQUOS® TV shut down after 3 hours?
The POWER CONTROL setting in the Display Menu allows you to save energy. When the NO OPERATION OFF feature is set to ENABLE, the power automatically shuts off if operation is not detected for 3 hours. To allow the television to operate continuously, the NO OPERATION OFF feature must be set to DISABLE."
I changed the menu setting this morning and didn't have a turn-off tonight. Thank you.
Two things are curious about this.
The 3-hour turnoff just started a couple months ago, to the best of my knowledge. But the Sharp is more than 3 years old.
The owner's manual calls this "No operation off" and says that it shuts the power down when there is no operation for 3 hours. I couldn't connect this -- still can't -- to actively watching the thing during what I would call normal operation that happens to extend past 3 hours. Besides, the manual also states that there is an on-screen count-down starting 5 minutes before turn-off. Never happened.
Anyway, thanks again, to everyone who responded, especially cdb.
No operation means no use of the remote. This is probably in case you fall asleep in front of the TV.
Jack
Edits: 09/18/14
Sometimes, say a sudden power outage when a TV is on and running, electronics gear does odd stuff, as in returning the TV to all the original factory default settings. Do you recall having a sudden power outage while the TV was on and running just before this 3-hour shutoff started? It obviously came from the factory that way as the default.
I don't remember one, but it could have happened.
I've now found two things. First, that too-cheap HDMI cables are not a good thing. The one between my Denon Receiver and the Sharp TV has an intermittent problem and has been replaced.
Second and more important. The Sharp turns itself off EXACTLY 3 hours after it was turned on. I've now timed it 4 times and there's no question about this. I'm sure the "why" resides somewhere in the menu/software and I just haven't taken the time yet to track it down. More specifically, there is a "No operation off" function that "allows the TV to automatically shut the power down when there is no operation" and the period after which it shuts down is 3 hours. Obviously there IS operation during the 3-hour period (I'm watching the damn thing), but this seems too weird to be coincidental.
More later. Thanks for everyone's help.
Perhaps the Sharp doesn't recognize "operation" if the unit is always playing audio via an external device (the Denon receiver) rather than its internal electronics. Why it suddenly figured this out after a lot of time (maybe 2 years) rather than immediately is another question.
I still think you accidentally got the sleep timer turned on in the menus somewhere at the 3 hour shutdown point. YOu need to go thru the menus and find the sleep timer. MOST modern TVs have a sleep timer built into the menus somewhere, and 3 hours would likely be the max length other than none at all.
David
You my be right. I plan to check all this out tomorrow. The manual, though, says that the sleep timer options extend only up to 120 minutes (i.e., 2 hours), and provide on-screen reminders starting within 5 minutes of turn-off.
You're probably on the right track, clever of you to measure the times.
My plasma has a "no activity" time-out: like for no active input, receives no remote signals, stuff like that, I've never used it. Look for some feature like that, maybe under a power-saving (sub-)menu.
I can certainly see this feature for a watt-sucking plasma, but I guess even for a LCD it saves a bit of power.
Unlike the sleep timer, which requires "planning", this is for when you forget to power off, or pass out.
If you make a SINGLE channel change and back during the three-hour period, does the TV still shut down at EXACTLY 3 hours from when it was originally turned on, or is it 3 hours from the point where you made the channel change? I need a stopwatch to diagnose this one.
Apparently the "timer" starts over after the last remote input. This is pretty much only for TV's (built-in tuner), rather than plain displays.
A display with this feature would probably call it something like "no signal shutoff", it would *not* be looking at remote control signals to trigger, just the A/V input signal.
Whether sleep timer or no activity shutdown, mine displays warning messages starting 15/5 minutes before shutdown, then every minute in the last 5. I don't use these features, haven't for a very long time, so I'm unclear on the exact details.
Now that I think of it, it would make sense that any kind of shutdown timer display these messages. So if you're not seeing them, it's probably not a shutdown timer, unless there's something built-in that's totally non-defeatable (doubt that, that would limit the display's application).
Could there be some kind of store/demo/etc. mode in effect that you have to cancel? Mine's a Pio Kuro so you know it's at least 5 years old, and I vaguely recall I had to turn off some kind of mode the TV was in when first received (new). You could only do this once without getting "advanced". It might make sense that some initial non-defeatable shutdown mode be enabled, without messages so it doesn't "scare" customers when it's on display. I'm grasping here...much easier to judge when in front of the gear...
Did you maybe accidentally set a timer to turn it off?
It could be several things and there is not enough information to really pinpoint anything. Does the audio still work when the display goes dark or is the TV completely dead? It is more than likely related to a heat issue of an aging part or component. You could try putting a fan behind it, preferably with the back cover removed (and even the shield over the boards removed) to see if it still does it, to get an idea.
I would check 3 things first: the inverters, the power supply capacitors and the display lamps and their connections at the lamps.
Measure the inverters and look at the electrolytic capacitors on the power supply board. Often you can just look at them and see that they are bad, or going bad, by their swollen case and/or leakage. If they look good but, the lamps and inverters also checkout good you will need to remove them and take measurements. If one or more is bad then replace them all (on the PS board). You can probably find a capacitor replacement kit on ebay or some other website for your TV model if you do not want to buy them separately. [It could also be an electrolytic capacitor on the processor board but that is not very likely.]
If it is one of the lamps or its connections it is more than likely the one at the top that takes all the heat from the rest below it.
I really appreciate your response. Here's a little more info, but I have to say up front that I'm too technically illiterate to perform the tests you suggest. I don't watch it all that much as I'm mainly an audio guy (audio system is completely separate, in another room).
The Sharp is a two-year-old flat screen unit that sits atop a stand. Lots of air circulation. Connections (mostly HDMI) to a nearly new Denon receiver, Oppo Blu-ray/DVD player, an Apple TV, a Comcast cable box and an ancient VCR. No timer. Everything works fine, no problems, except when the TV dies (screen goes black, pilot light goes off). Sound stays on, because it's provided via the Denon receiver. Turning the Sharp back on, it operates as before. Until the next time. The Sharp has never turned itself off more than once in any given day, usually after playing for an hour or two.
After this happened a couple times, I checked the entire unit for any hot spots. Nothing was ever more than mildly warm. Checked repeatedly for bad connections (including AC) and never found any.
Because the problem is so intermittent, I'm now of the opinion that it needs to get worse before calling somebody knowledgeable for help.
You may have lots of circulation on the outside but one of the main reasons components in flat screen TVs and computer monitors go bad is because they are so thin that heat easily builds up and the components destruct long before they do in larger pieces of equipment. If something is overheating inside you are not going to feel it on the back of the plastic cover.
I agree, because intermittent problems are difficult and time consuming to trace it may make more sense to wait for it to get worse.
One thing I would try in the mean time is to disconnect the cable box, Apple TV and the Oppo and play a tape (or several) in the VCR to determine if the TV still shuts off.
Also vacuum cooling holes and slots with brush attachment of your vacuum.
good luck
Does it go off during a movie. I believe most go off in about 1/2 hour with no input...
Just did it, about 20 minutes ago. I was watching a baseball game.
?
that would change everything...
The Sharp was bought for me by a consultant who had done a major video upgrade for my wife ... and then disappeared on us. At the time it didn't matter all that much to me (I'm audio, she's video) and it didn't occur to me until latter that I never got an invoice. Yeah, pretty stupid.
But things are looking up. See my newer post directly under my first one.
Smart TV.
Read a book!
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