Mr. Nice; I have a Sony KV32XBR400 TV which has worked flawlessly since we purchased it in late 2000, until the last few days. Randomly, it will now not display any video, but the sound works fine and the channels can be changed successfully, there is simply no image. Last Thursday is when the problem first appeared. I moved the TV and removed the back and carefully cleaned out the dust from the circuit boards, but I couldn't get it to display any video. I unplugged the unit Friday night and turned it on Saturday morning with the main power switch, not the remote, and the video came up properly. I let the tv play for an hour or so and turned it off with the remote; I them immediately turned it back on and put it in "screen test" mode, based on the service manual. The video came up properly and the self-diagnostic screen displayed all zeros (0) for +B OCP, +B OVP, V Stop, AKB, LOWB, H-STOP and WDT faults. I turned the unit off to quit/clear the self-diagnostic screen and then back on and I got good video. I left the set on all day and it worked normally. Sunday I turned it back on with the remote and it worked properly; I left it on all day. This morning, Monday, I tried to turn it on with the remote and the video would not come up, but again the sound was okay. I've tried turning it on several times during the day and it won't "light" up. Because the diagnostic test looked good, is there a chance there's a high voltage relay that aperiodically isn't closing to allow voltage to the tube? I read one of your repair solutions for a somewhat similar problem where you suggested changing one or two IC's, would that be a possible solution for my set? As I mentioned, I have the Sony service manual. If you can give me some repair suggestions, I would very much appreciate it; the TV has had an excellent picture so I really don't want to replace it.
Thanks in advance, sorry for the long note but I wanted to describe the problem and the diagnostics I've been able to run.
Best regards,
Bill Arend
[email protected]
It might be a bad picture tube, i think it costs around 1000$ for replacement
Hi,
Since this is a Sony TV, if there is a problem with it.
It normally indicates with a code.
I mean, does the standby LED blink?
If so, how many times does it blink?
Its a code which you can check with Sony to find out what might have gone wrong...
:)
Thanks for updates.
Five blinks means..
 AKB circuit (automatic kine bias),
Techical detiails:
Check video out, Q705, 732, 761 and other components on the C board, also check Q218, 219, 220 on the A board. In addition, unit could be in IK blanking, try turning up screen slightly.
You do not want to try it on your own to fix it.
Get a authorized repair man. Tell him this code. and get it fixed.
:)
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1. Try this - hold the menu button down for 10 seconds. TV should power up; you will have to turn off front panel buttons on menu.
2. You can also try a hard reset: Unplug TV from AC mains and remove all cables from TV. Wait about 30 minutes and replug to AC power and redo the cabling. Switch on the TV and see if it works..
Weak capacitors often go out of spec when they cool, thus preventing a section of the power supply from firing up properly again. There is a simple trick...just warm the back of the TV with a hair dryer for 5-7 mins after you have unplugged the TV. Look for the little areas of holes in the back panel of TV. Use these as your guide at where to use the hairdryer, but don't hold the dryer too close (say 5-6inches away). (Make sure the dryer is on High heat). If the TV doesn't turn on after you have heated it up (like it tries to come on but then turns off) you need to unplug the TV again, this resets it. And repeat those steps till it works. Resetting the TV after it fails to turn on is the key.
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I tried item 1) and it didn't work, the TV did not turn on but maybe I didn't understand your suggestion well enough. I pressed down on the "menu" button on the remote for approx. 20 seconds while aiming it at the TV. Can you explain further what you mean by "you will have to turn off front panel buttons on menu". I left the panel closed when I held the "menu" button down on the remote.
I've tried your item 2) numerous times over the weekend and like I said in my first note, sometimes the TV would power up fine and other times it wouldn't e.g. this morning after the unit had been off all night and unplugged.
Mr. Nice; I have a Sony KV32XBR400 TV which has worked flawlessly since we purchased it in late 2000, until the last few days. Randomly, it will now not display any video, but the sound works fine and the channels can be changed successfully, there is simply no image. Last Thursday is when the problem first appeared. I moved the TV and removed the back and carefully cleaned out the dust from the circuit boards, but I couldn't get it to display any video. I unplugged the unit Friday night and turned it on Saturday morning with the main power switch, not the remote, and the video came up properly. I let the tv play for an hour or so and turned it off with the remote; I them immediately turned it back on and put it in "screen test" mode, based on the service manual. The video came up properly and the self-diagnostic screen displayed all zeros (0) for +B OCP, +B OVP, V Stop, AKB, LOWB, H-STOP and WDT faults. I turned the unit off to quit/clear the self-diagnostic screen and then back on and I got good video. I left the set on all day and it worked normally. Sunday I turned it back on with the remote and it worked properly; I left it on all day. This morning, Monday, I tried to turn it on with the remote and the video would not come up, but again the sound was okay. I've tried turning it on several times during the day and it won't "light" up. Because the diagnostic test looked good, is there a chance there's a high voltage relay that aperiodically isn't closing to allow voltage to the tube? I read one of your repair solutions for a somewhat similar problem where you suggested changing one or two IC's, would that be a possible solution for my set? As I mentioned, I have the Sony service manual. If you can give me some repair suggestions, I would very much appreciate it; the TV has had an excellent picture so I really don't want to replace it.
Update: The TV turned on successfully Tuesday after being off all night. I turned it off and on several times and it worked fine. Wednesday morning after again being off all night, the video would not come up. Again the same story this morning Thursday, the video would not come on. The instant I hit the "power on" button on the remote, the "standby" LED blinks five quick times and then goes steady, there is no repeating of the blinking pattern.
Thanks,
Bill Arend
I know the picture tube is one giant capacitor, how do I test or determine whether it's failed?
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