I have an LG47 50YD LCD TV with vertical scan loss. Can you help with a schematic?

moved you out of cars to TV
no model TV told, at all off rear label.
there are 2 causes (dead picture and dead sound)
PSU dead
PSU overloaded
there are tested for all
check all DC rail voltage to spec.
then if one fails, we disconnect load to this DC pin and see if PSU wakes up. if does the load removed is bad
the service manual cover all this (schematics)

samsung lcd tv: vertical color lines *PLEASE HELP* - Forums - CNET

www.cnet.com > Forums > Samsung

CNETJun 11, 2015 - samsung lcd tv: vertical color lines *PLEASE HELP*. by justinwu86 / March 31, .... In reply to: Vertical colored line on left side of screen. yeah the pannel has ... Red/Blue vertical lines on display
Jun 11, 2015
Vertical Lines help samsung led lcd tv
Oct 4, 2014
Thick vertical line in Samsung 52' TV
Jul 5, 2013
Thin vertical line on Samsung LCD TV
Feb 10, 2010
More results from www.cnet.com

Hi.

The TV starts in forced standby. The state is also called "Protect Mode". Protect mode kicks in whenever an internal fault is detected. The error is detected by controller circuit and the PSU is forced in standby mode, shutting down all voltage lines apart 5VDC to keep standby on.

First try disconnecting the power cord for ten minutes, reconnect after ten minutes and restart the TV with no device connected.

If that does not help it means that there is an internal fault and that the TV must be tested and repaired replacing the defective part.

The defective part is usually the PSU. Among components that fail quite commonly there are the capacitors on the power board. If the capacitors look swollen or if there is trace of damage on PSU board, then the affected parts must be de-soldered and replaced. If there is no evidence of damage at a glance the parts must be tested using a multimeter and following schematics from service manual.

If you need to call a technician use the phone number listed on the owners manual or on the manufacturer support web page.

Regards.

Ginko

Considering the slow discharge of the cap, it is probably good and without an RCL meter with loss capabilities, it would be tough to condemn it.
In most cases I've seen, the larger filter caps are not at fault but rather caps in the range of 4.7-100uFd that are used in the feedback path. The voltage ratings are seldom over 50VDC. These are exposed to high frequencies and if a standard electrolytic is used (they are cheaper) they will eventually fail due to the decay of the chemicals in them.
You might check for a radio amateur club in your area since one of the members might well have an RCL bridge/meter with DF capabilities. If you find one with more than one frequency range, a bad cap will show a major decrease in capacitance and increased losses at the higher frequency.
Good luck-

Good Day,

This model is equipped with a self-diagnosis feature to help with diagnosis of shutdown problems. To activate this turn the unit on let it shutdown then press the input and menu buttons on the front panel simultaneously and hold them in for 5 seconds after 5 seconds the power LED on the front panel will blink a two digit sequence. This will be one set of blinks a short pause then another set of blinks, this will repeat 5 times.
1 - 2 = no error detected
2 - 1 = X-ray protect (high voltage or beam current)
2 - 2 = Short protect (short protect monitors low voltage supplies)
2 - 3 = Deflection protect (this could be loss of vertical or horizontal deflection)
2 - 4 = Vertical protect (usually loss of vertical from the source)
1. SHUTDOWN AT POWER WITH SELF DIAGNOSIS ERROR 2 2. CHECK FOR LEAKY C9A60 470 PF 1000 V PART # 154P400030, PARALLEL TO D9A57 ON THE POWER PCB (NOT SHOWN IN THE SCHEMATIC).

2. SHUTDOWN AT POWER WITH SELF DIAGNOSIS ERROR 2 2. CHECK FOR OPEN FUSES F9A04 AND F9A05 PART # 283P043090 ON THE +24 AND -24 VOLT LINES. IF THE FUSES ARE OPEN THE CONVERGENCE OUTPUT CIRCUIT WOULD BE SUSPECT.

3. SELF-DIAGNOSIS INDICATES SHORT PROTECT. CHECK FOR A SHORTED IC4B01 PART # 270P261020 (VERTICAL OUTPUT) LOADING 24-VOLT SUPPLY LINE. LOCATED ON THE MAIN PCB.

I hope this was helpful, BIG IRISH.

The symptoms you describe are actually 2 different issues. The easiest way to address this is to attack the vertical problem then if the other still exists, we will address that one. I should be able to provide you with details, but I will need the model number. Please update this with the model number and further details and instructions will follow.

Thanks,
Dan

I think you missed one cap. Look for another 1ufd cap close to the jungle chip. It will have the circuit designation in the 300's like the others in the vertical circuit. It is just not located close by. I think that one will fix it.I don't have the service data with me so I can't give you the exact designation.
Dan

Hello bouloulou, Well let me tell you what you have is a loss of Vertical Linearity. This could be cause by a power supply issue or by inproper filtering of the dc voltage used to supply the vertical section of the TV. There used to be a control which allowed you to adjust this along with Vertical Size which controled the bottom of the screen. These days the signal processor chip takes care of this along with a few capacitors. I woould suggest that if you do not have a background in electronics that you take the set to a shop for repairs, If you do have a background in electronics, get a schematic for this set and the use your multimeter set to DC volts to measure the DC levels in the vertical section of the TV. Also you will need an oscilloscope to measure the ripple voltage on the DC power supply the schematic will show you how much ripple is allowed. I hope this helps. Thank you, Shuttle83

make checks on your vertical it could be getting too much voltage replace it along with some cap around that are not filtering the voltage to the ic.because it have cause damage to your vertical change all related components in that circuit also check the related circuits.you can get a schematic for your set at www.samsphotofact.com good luck