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Discussion Starter · #1 ·
i think this may be a fairly common TOSHIBA crt tv problem....can someone please help me with this? >


i recently acquired a TOSHIBA CZ32V61 32'' crt tv...it was built in mid 1999....it worked well for about 2 days, then while on and working properly, it went to a black screen with audio and the red front panel power led was flashing.....since then it sometimes works properly with good video/audio but almost all other times it will turn on with the front panel power led flashing and has a black screen with no audio....

there seems to be no pattern or code to the front panel red power led flashing... it flashes about at about a '1 second ON/1 second OFF' rate.....

the crt guns are 'lit', u can see them glowing...and when u power OFF the tv u see the video 'collapse and fade away' as tho it was working normally....so i think most or all of the high voltage section is working properly.....

i also noticed an infrequent minor 'flickering' in the video when it was working properly....i'm guessing it may have a bad solder joint or loose connector somewhere.....tapping on the chassis when it is working sometimes makes the pic jump....


i also have a 36 inch TOSHIBA CN36G90 crt tv with similar (but not identical) problems....i re-soldered more than 100 circuit board connections on that tv with no effect....


i've been researching this as best i can in my spare time and i've found what seems to be a lot of other people who have this 'front panel power led flashing & no video' TOSHIBA crt tv problem....but i've found no real fix or solution....


its a nice large tv with a lot of life left in it otherwise, so i'd love to find a fix for it....any ideas?


thanks!
 

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It could be a tuner failure. Does it display the OSD/menu or does it display nothing?
 

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Discussion Starter · #3 ·
theres no OSD (on screen display) menus at all....its just a black/blank screen....and no audio....


but, as i said, the 1st time it failed the video went to black but there was audio....since then its been no audio or video....i dont think its the tuner....


so many of these TOSHIBA tv's of this age (about 8 to 12 years old now) have failed in a similar way that i'm thinking its a well known problem with a possibly easy fix....
 

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Okay so we're ruling out the tuner. You say the CRT guns are lit - that means filament voltage is present. But it does not necessarily mean that high voltage is present as well. Could be flyback, video output transistors or video amplifier IC.


The flyback should have two or three knobs. Using a well-insulated screwdriver turn the one labeled "Screen". Do bright white diagonal lines appear on the screen when you do that?
 

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Discussion Starter · #5 ·
thanks for the input, Th3_uN1Qu3...i know where the screen drive pot is and i'll check that asap....


i temporarily put the tv back together to move it to the basement to work on it later asap....this tv is a monster to move and work on...its very heavy and awkwardly large...it takes at least 2 people to move it safely....


but i bet when i try your suggestion it will have no effect....i suspect something is 'suppressing' the video (and audio) in some strange uncommon way....a logic circuit somewhere (in an IC?) is sending an error message to the video deflection control circuits in another IC somewhere? or a simple loose connector or bad solder joint somewhere?....or who knows what?


this same (or very similar) problem has apparently happened to so many of these TOSHIBA tv's that i'm hoping a common solution has been found and it will be shared with us here....a lot of large tv's could kept out of the landfills....


does anybody know of other appropriate forums or boards to post this problem at?
 

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Yes, it could very well be some protection tripping and shutting down the video. Try getting hold of a service manual, it should have some procedures listed.


I'm not too fond of all those protections - i prefer the "if-something-is-wrong-there-should-be-smoke" design. It's so much easier to spot a burnt part and check for shorts in the area then easily find what caused it to burn, and two swaps later you would have a perfectly working TV.


Also those protections have the habit to cause parts to fail "silently", and on ICs these failures can be difficult to spot. If you can't find the service manual look up datasheets for all major ICs in the set, and check voltages according to the datasheets.
 

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I find this funny since I have almost the same TV and bought the thing in August of 1999 and then in August 2009 it starts doing this. At first things would come back after 5-10 minutes and work fine until turned off, but now it tends to just stay blank. I was about the give the TV away to freecycle, but if anyone found out anything new it would be nice to hold out on having to buy a new TV for a while.
 

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Discussion Starter · #8 ·
sounds a lot like my TOSHIBA problem, veekay ....the more i look into this the more i see of this problem with many many TOSHIBA tv's....it seems craigslist has far more TOSHIBA tv's for sale (or even for free)than any other brand and i bet its because of this kind of common problem....i will continue to search for a fix when i have time and post it here if i have any success....


i wonder if TOSHIBA was sued in a class-action for this and lost...if not, they should have been....i have two large screen high-dollar dead TOSHIBA tv's here now....a 32 inch and a 36 inch.....and a 3rd 32 inch thats probably about to die....i will never buy another TOSHIBA product!


supposedly GE was sued for some kind of similar wide spread tv problems a few years ago and lost that case....
 

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Anyone have a proven uni for this BEEEAAST? I need something to rule out a bad IR receptor.
 

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Alright. I've tried every Sony, Motorola and Phillips/RCA universal remote and code and still nothing.


Any suggestions? Without going Harmony (To much $$$)


Sorry. Need compatibility for Motorola DCT700 set top box or individual remote for CRT
 
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