Re: LG 50PG10 Sound No Picture.
both buffers out:
Vy 0.01V across resistor : 20V referenced to ground
Vsc 135.2V...
Hawk2112
Member
Last Activity: 12-13-2020, 10:30 PM
Joined: 06-19-2010
Location: Victoria
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Re: LG 50PG10 Sound No Picture.
Was mis-typed Vsc is 135.2V
Still checking but no luck so far finding the cause of the Vy being so low....Leave a comment:
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Re: LG 50PG10 Sound No Picture.
VY R201 5.21V across resistor
Vsc R202 153.0V " "
C213 135.1V on right leg
I am assuming R201 is way to low?...Leave a comment:
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Re: LG 50PG10 Sound No Picture.
I do hear a buzzing when there is no audio playing. Checking the points you posted in your last response shortly....Leave a comment:
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Re: LG 50PG10 Sound No Picture.
These are the only refs to Vsc vy etc but ccan't find any test points labeled for them...Leave a comment:
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Re: LG 50PG10 Sound No Picture.
Any ideas where to check next or is this just a dead screen maybe?Leave a comment:
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Re: LG 50PG10 Sound No Picture.
all the test voltages and points that I check. Was not able to find the ones Vsc, Vz, Yup
Vs 191v at all points
Va 63v at all points
M5v 4.96V
5v_det 5.02v
RL_ON 3.22v
M5V_ON 3.75v
all fixed voltages ie if it says 12v or 5 v or 16.5v also correct.
AC_DET 4.95V
VS_ON 3.26V
AUTO_GND 3.25V
There are others leaving the Ysus down to the bottom board
XR 16.52v
XC 16.57v
XL 16.50V
+15v...Leave a comment:
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Re: LG 50PG10 Sound No Picture.
back of the panel is
5V
Va: 65
Vs: 193...Leave a comment:
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Re: LG 50PG10 Sound No Picture.
Vs 191v at all points
Va 63v at all points
M5v 4.96V
5v_det 5.02v
RL_ON 3.22v
M5V_ON 3.75v
all fixed voltages ie if it says 12v or 5 v or 16.5v also correct.
There are others leaving the Ysus down to the bottom board
XR 16.52v
XC 16.57v
XL 16.50V
Will get the rest after work tonight.Leave a comment:
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Re: LG 50PG10 Sound No Picture.
No just a black screen.Leave a comment:
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LG 50PG10 Sound No Picture.
I have searched the forums and ran every test I found to no avail.
All voltages are good. Test pattern results in black screen. Pulling the top/bottom YSUS produces nothing. I have tested every fuse etc I can find but there is no image on this thing.
Any help would be greatly appreciated.... -
Re: Samsung BN44-00175A SMPS clicking (No 5.3V)
Lookimback was right and upon better cleaning 25H3LL can been seen so they are Power MOSFET for DC/DC conversion.
I reflowed the ICs and its working again. I am going to order the chips and have them on hand if/when it acts up again....Last edited by Hawk2112; 08-09-2015, 11:10 PM.Leave a comment:
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Re: Samsung BN44-00175A SMPS clicking (No 5.3V)
Tried everything but the surface is rubbed away for some reason....Leave a comment:
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Re: Samsung BN44-00175A SMPS clicking (No 5.3V)
Attached some new pics. I have a small IC that is causing the issue but it appears to have the ID removed.
If I apply my soldering iron tip to the top of the IC for 5 sec, the 5.3V rail starts normally and the SMPS runs fine (for a while).
PIC#1 idents the 5.3V rail and the IC in question.
PIC#2 is a closer shot of the IC.
Any suggestions on how to proceed or is this a lost cause?...Leave a comment:
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Samsung BN44-00175A SMPS clicking (No 5.3V)
Have a 50inch plasma with a faulty power board. I replaced the standard faulted caps and it worked again for 3 more weeks but has failed again.
I have replaced the caps again to be safe (CB814/14 and CX834/35) with Panasonic FM's but still not joy. LED fault code is for the 5.3V
(While Clicking)
STBY =5.195V
Vs =0.2V <-- I understand this one won't come up until this Vs_On is +5.3V
Va =65.1V
Vg =15.07V
12 =12.0V
Vamp= 18.2V
5.3V = 0.72V <-- only one out of range
Fan = 7.92V
I have continuity... -
Re: Samsung BN44-00175A Not Powering Up
Ok so it worked for a while and back to square one. I have replaced (again) CB814/14 and CX834/35 with Pan FM series caps.
voltages are
(While Clicking)
STBY =5.195V
Vs =0.2V <-- I understand this one won't come up until this Vs_On is +5.3V
Va =65.1V
Vg =15.07V
12 =12.0V
Vamp= 18.2V
5.3V = 0.72V <-- only one out of range
Fan = 7.92V
5.3V caps have continuity (Barn01 asked me to check)
Not sure what to check next.Are there schematics available...Leave a comment:
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Re: Samsung BN44-00175A Not Powering Up
Have to order the caps (panasonic FM). Do you advise to up the Voltage to be safe as well. ie 2200uF 16V instead of 10V ?
While I am waiting I retested the pulled ones and all measured good (capacitance) but my little ESR only goes to 2 digits so read as .00.
Soldered them back in and retested. Power comes on with no error 5.3V is good and Vs comes up to 202.6 V when I pull up the VS_On (using the 500ohm)
Set has been on for an hour now and holding. I will replace the caps when they arrive but...Leave a comment:
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Re: Samsung BN44-00175A Not Powering Up
Damn lol.. they are GP. Will swap them out for Low Imp as soon as I can get some today.Leave a comment:
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Re: Samsung BN44-00175A Not Powering Up
(While Clicking)
STBY =5.195V
Vs =0.2V <-- I understand this one won't come up until this Vs_On is +5.3V
Va =65.1V
Vg =15.07V
12 =12.0V
Vamp= 18.2V
5.3V = 0.72V <-- only one out of range
Fan = 7.92V
Will pull the board back out and look closer at traces and the IC's on the heat sinks
You asked Barn01 if there where any 5 lead ICs on his and yes there are 2 on mine.
I did replace the same caps as Barn01 and then checked the remainder.
Really...Leave a comment:
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Re: Samsung BN44-00175A Not Powering Up
Thanks,
Ok PS_ON grounded and the relays multi-click and then DB error flashes.
Flash error is 2 = 5.3V error and it is measuring 0V.
everything is 0V or falling to 0V (ie Va is slowly dropping as caps discharge)
The only correct voltage is the STBY at 5.2V
Hope this helps narrow the fault but I guess it also confirms the SMPS is the problem. Hoping I can find the component and fix rather than order a whole new supply.Leave a comment:
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