Hi: I have a Panasonic CT-27D10B 27" tv that exhibits the following:
1) set is operating normally, then, instantaneously it shuts off (as if someone used the on/off switch to turn it off). It will come back on anywhere from 10 seconds to maybe 5 mins. Sometimes it will display the setup screen, sometimes not.Any ideas what may be causing this?
Thanks John
Start with the mains as the their removal for whatever reason/problem usually results in many sets going into the setup mode upon restoration of the mains.
That would be my inclination as well...however, given the behavior of this beast, what do you think would be the cause? board trace? solder joint? or a component? I can't even guess what would be causing the problem - it does not seem to be temperature related. Pressing on the board when it dies does not seem to bring it back. There is a thermistor right after the PS section. I haven't figured out what it does - suggestions? Thanks John
Hard to say as it could be any of the aforementioned. I would rule out a physical problem first. Get the set in a place where you have lots of light, a bright portable light, can easily see both the top and bottom of the board and where you are comfortable and give it a good visual. Have a magnifying glass handy too. I have one of those stereo magnifying visors and frequently use it to inspect solder joints.
The thermistor might be used in the degaussing circuit or as a current inrush limiter. Barring failure on your part to find a physical defect you might want to get a schematic that has some voltage and scope test points. I've run into situations where poor solder joints or PC board pass thru connections were not discernible even under magnification (not saying this is your problem.)
connections on the relay and on the thermistor were common problems also resolder the vert o/p ic as their connections will break as well
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.