Re: 37lg7000 sound. No picture but backlight on.
Vgl -8v
Vgh 24v
Vgl -8v
Vgh 24v
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Re: 37lg7000 sound. No picture but backlight on.
invalid, deleted.Last edited by Hamie; 10-03-2015, 01:22 PM.Comment
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Re: 37lg7000 sound. No picture but backlight on.
Just done that. the readings are as aboveComment
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Re: 37lg7000 sound. No picture but backlight on.
Ok so far the voltages appear accurate.Comment
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Re: 37lg7000 sound. No picture but backlight on.
So what's the verdict? Does that mean tcon good?Comment
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Re: 37lg7000 sound. No picture but backlight on.
Finally check the gamma test points.
Located here, and also to the left (the ones under the white line you were testing previously.)
22 in total, post back results like:
V1-
V2-
V3-
EtcComment
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Re: 37lg7000 sound. No picture but backlight on.
V1 16.5v
V2 16.2 v
V3 14.4v
V4 13.6v
V5 5mv
V6 12.6v
V7 23mv
V8 11.5v
V9 10.7v
V10 8.7v
V11 8.7v
V12 8.3v
V13 8.3v
V14 6.3v
V15 5.5v
V16 27mv
V17 4.3v
V18 27mv
V19 3.2v
V20 2.5v
V21 0.6v
V22 284mvComment
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Re: 37lg7000 sound. No picture but backlight on.
thers some odd readings there never saw any mv beforeComment
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Re: 37lg7000 sound. No picture but backlight on.
V10 - V13 don't look right either.Comment
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Re: 37lg7000 sound. No picture but backlight on.
Def mv.
So what's the next move?Comment
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Re: 37lg7000 sound. No picture but backlight on.
some maybe mv im still learning myself but have never saw any threads with mv in the gamma readings im sure someone will comfirm later maybe tom or budm will have a idea if hamie isnt sure?Comment
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Re: 37lg7000 sound. No picture but backlight on.
In my experience the voltages should drop gradually.
So if those readings are correct you have have a faulty t-con.
Going by the fact I can't seem to find anyone selling one would usually suggest that this board has quite a high failure rate.Comment
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Re: 37lg7000 sound. No picture but backlight on.
Double checked all mv ones and they are all in the mv range. So shall I be looking for a tcon?Comment
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Re: 37lg7000 sound. No picture but backlight on.
If this was my set the tcon is usually the cheapest of the boards so yes i would probably change it. Make sure you get one with a returns policy just incase its faulty already failing that you may have to look for a smashed screen working set and use the boards from that.Comment
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Re: 37lg7000 sound. No picture but backlight on.
Not really sure what to say. Gamma readings are there, also they are bad, but that shouldn't cause a no picture, bad gamma just causes a bad solarized pic. Would be nice checking the lvds cables in and out of the Tcon..Comment
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Re: 37lg7000 sound. No picture but backlight on.
So if the readings are good and screen is blank can I assume the main isn't sending any graphics out?Comment
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Re: 37lg7000 sound. No picture but backlight on.
The gamma readings aren't good, but they are there. That shouldn't cause a black screen. Yes and no, that's why I suggested to use the oscilloscope on the LVDS first place. That's the only 100% way I know how to check a main or Tcon for video. I usually don't bother checking the gamma unless I have trouble with the gamma. More important to have video on the screen first place.
Last idea I have is that you check each lvds output on the main and the Tcon. You would have to measure each LVDS channel pair for 350mV with your DMM. So far you still don't know yet, if you actually have any video coming from the main board or not.Comment
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Re: 37lg7000 sound. No picture but backlight on.
Hmm. Think I'll order a tcon and try.Comment
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Re: 37lg7000 sound. No picture but backlight on.
Quote ! Last idea I have is that you check each lvds output on the main and the Tcon. You would have to measure each LVDS channel pair for 350mV with your DMM. So far you still don't know yet, if you actually have any video coming from the main board or not.
capleaker is this easy to do and easy to find the channel pairs? do you just test across the pairs?Comment
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Re: 37lg7000 sound. No picture but backlight on.
Bad gamma can cause many faults.
Solarisation being one of them.
Image to dark, image too light etc.
I had one fairly recently where the image started off a bit dark then faded out to to completely black.
Therefore with gamma voltages as bad as the ops I'd be surprised if it wasn't caused by the tcon.Comment
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Hello everyone,
Ive got a UE60KU6079 on the workbench that is giving me some headaches trying to troubleshoot.
The previous owner stated that there had been white dots on the screen which from the description sounded like some lenses fell of the backlight LEDs.
He had opened the TV from the back, trying to get to the backlight, supposedly gave up, reassebled everything and gave the TV to me.
I expected the worst like ripped COF cables or a cracked panel but could not find anything like that yet.
Anyway I still fully expect that there has been something seriously damaged... -
this tv is throwing me for a loop. do samsung tvs no longer have the backlight self test feature built into the power supply?
i tested the backlight with my LED tester and it lights up both strips. one of them reads 100v and the other reads 63.7v.
unplugged mainboard from power supply but left backlight plugged in, and then plugged psu wall power in. expected to see backlights light up but see nothing.
according to how ive diagnosed in the past, this would almost always be a bad power supply. replacement power supply was cheap like 20$ from ebay. but still i get not even... -
Hi, I have a Samsung UE50TU with:
- sound and backlight, but no picture
- when it arrived, it had a picture for a few seconds
- it keeps rebooting
- without ribbon cable between the two panel boards, it does not reboot but I have no picture
- without cable between mainboard and lcd panel, it does not reboot (but obviously i have no picture)
- when i try a tape fix, its keeps rebooting, unless I tape off pin 1 (the innermost pin). In that case it does not reboot but I have no picture.
- without cable between mainboard and lcd panel and with a jumpered... -
I have a 60 inch Samsung UN60EH6000F flatscreen TV. The screen went black a few months ago Sound is good, backlight is good, no menu. I replaced the TCon board with a used board purchased from Ebay. It worked fine for a 3-4 months, then the screen started ‘fading' back. Once again, sound is good, backlight is good, no menu. However, this time the picture looks fine for about 10-15 minutes, then fades back. If I power cycle the TV, the display reappears, for another 10-15 minutes, then fades black again. Repeatable ever time.
I ordered a supposedly ‘new' Tcon board this time, and... -
Hey Guys,
So a few months ago my Sony XBR 49x900e TV screen stopped displaying the picture but the backlight comes on and I still get sound when I use the remote and navigate to certain apps. I haven't checked anything with the meter yet but started with ordering some replacement boards. I've tried replacing the BMKS board (used from ebay) and also completed the firmware upgrade based on Nicks TV repairs youtube video. I've also replaced the TCON (twice) and PIB.
All of these changes have resulted in the same issue with no picture. I've also tried disconnecting the ribbons...
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