In detail: do-it-yourself repair of Samsung TVs with a return line from a real master for the site my.housecope.com.
Samsung has long been one of the most popular brands sold and serviced in Russia.
The choice of buyers is justified by the favorable price-quality ratio of the equipment, and the popularity among repairmen is due to many factors that determine the simplicity and ease of repair and maintenance.
Despite the variety of models, Samsung TVs for technicians and service engineers remain uncomplicated and predictable in repair, and the manufacturer's timely technical support with components, modules, documentation and software greatly facilitates and simplifies diagnostics and repairs.
Since the beginning of the nineties of the last century, the craftsmen have accumulated rich experience in repairing Samsung TVs, which was discussed and preserved on the Internet in numerous conferences and blogs of repairmen.
Typical defects of some models sometimes caused controversy and deserve special attention in considering the causes of malfunctions and methods of their elimination.
In this series of articles, it is planned to consider the most common malfunctions of Samsung CRT TVs from 2000 and the most popular LCD TV models in the practice of repairing.
There is no need to consider the problem of electrolytic capacitors in the rectifier filters of power supply modules, since this is a massive trend characteristic of the first generation of LCD TVs. It should be noted that in LED TVs, the problem with electrolytic capacitors is less common. Perhaps this is due to the lower consumption of LED backlight power converters.
Video (click to play). |
Operation of some first generation Samsung LCD TVs with defective power filter capacitors may cause software failure. At first, the settings for the channels may disappear, sometimes specific distortions appear in the “Cinema” mode, the screen backlight adjustment may not work correctly.
Often there is a complete failure in the software and the TV is no longer included in the operating mode.
In such cases, after repairing the power module, it is necessary to replace the contents of the EEPROM memory.
One of the most popular power supplies in repair is described separately in the article Typical faults BN44-00192A. In addition to defects caused by a malfunction of electrolytic capacitors, we note two more typical malfunctions of this module. Ring cracks in the soldering of the terminals of the switch-on transistor from standby mode, as well as breakdown of the sealant with subsequent short circuit and damage to the 2200pF capacitor and breakage of the 0.22 Ohm resistor in the power supply circuit of the key transistors of the converter.
Noise in the image in the form of curved oblique stripes associated with poor filtering of the tuner's power supply is eliminated by replacing the 100uF 16V capacitor on the main board. In this case, there is no need to change the capacitor in the tuner. Sometimes the masters do the opposite, due to insufficient competence, then such a replacement will help for a short while.
Another popular typical malfunction of some Samsung LCD models is the use of the AS-15 gamma correction chip in the T-CON board. AS19. The defect is associated with distortion of color transitions. The image becomes lighter and in places looks like a negative.
The latest LCD models, in particular the SMART-TV, have problems with BGA soldering technology for highly integrated chips. In such cases, malfunctions may occur, usually manifested with warming up, which are caused by a violation of the contact of the chip pins with the corresponding pads on the board.
The malfunction of the LCD matrices is perhaps a separate topic for discussion, but it makes sense to briefly consider some of the external manifestations of its defects.
In most cases, these are straight vertical stripes in certain areas of the screen or throughout its entire area. Stripes can be different, both colored and black and white of different thickness.
Sometimes the nature of the stripes changes with external mechanical stress. Freeze-frame images may appear.
Such matrix defects are associated with broken contacts in the connections of the loops, which can sometimes be restored with warming up.
Repair of the matrix in such cases is associated with its disassembly and restoration of contacts in loops or duplication of connections with external conductors - a complicated process, not recommended by manufacturers and may not always be a successful and reliable solution to the problem.
Due to the fact that the price of the matrix is quite high, it is more than half of the cost of a TV, in most cases, owners of post-warranty TVs refuse to replace the matrix due to the economic inexpediency of repair.
In many models of LED TVs of the 5 series, panels (matrices) with backlight LEDs of sufficiently low quality are installed, or the current in the LEDs is incorrectly calculated. This currently popular typical defect can manifest itself already in the first year of operation. In this case, there is simply no picture.
In authorized service centers, on the recommendation of the manufacturer, they change the LED rulers and limit the current in the LED drivers so that the TVs work out at least the warranty period. And in post-warranty cases, this problem is solved by the craftsmen in different ways, depending on their qualifications and contractual conditions with the owner.
Some explanations and recommendations can be found in the article in our article Repair of Samsung, LG LED-backlights.
Of the most common malfunctions of Samsung CRT TVs, there are several associated with the low reliability of CRTs and their deflecting systems (OS).
The consequence of shorting the filament with the cathode of the kinescope (usually green) is eliminated by isolating the filament from the mass and organizing its separate power supply (2-3 turns per TDKS core). In this case, do not forget to use the standard filament current calibration resistor.
In kinescopes with a flat screen, diagonals of 20 inches and more, a short circuit between the accelerating electrode and the modulator (G2 and G1) often occurs, which is accompanied by the absence of an image.
Fortunately, such short-circuits, in most cases, can be easily eliminated by the usual old-fashioned methods popular among repairmen.
It is more difficult with a short circuit in the lower case deflecting coils of the CRT. At the same time, the line transistor short-circuits, usually immediately upon switching on. In some cases, you can see smoke from under the throat of the OS, feel the characteristic smell, the transistor (HOT) overheats at this time.
A lot of trouble in many models of Samsung CRT-TVs of different diagonals is delivered by the elements of the IOC capacitive divider of the horizontal sync pulse formation circuit. In such cases, the limiting resistor often burns out to charcoal, sometimes damaging the board section along with the conductive tracks.
In cases with “floating” defects, when it is not possible to detect poor contact in the soldering of the element leads, it is necessary to remember the specificity of the metallization of the holes in the power circuits of the horizontal scan, which is characteristic of Samsung CRT TVs.
The contact of the metal sleeve with the copper pad of the board is often painted over, sometimes it is faster to detect sparking in this place than to see an annular crack with a magnifying glass.
Most often, such a breakdown of contact occurs at the place of soldering of the contact pad with metallization of the collector connection of the line transistor.
Typical malfunctions of some common models made on standard chassis can be considered separately.
Pages will be added as the material is prepared.
Typical defects and repair of Samsung chassis KS1A - From the practice of repairing Samsung KS1A TVs.
Typical defects and repair of Samsung chassis KS2A - From the practice of repairing Samsung KS2A TVs
According to the functional composition of CRT (with a kinescope) and LCD (LCD) TVs, separate sections have been created on the site, where modules and elements for well-known and popular models for repair are indicated in the tables:
Composition of Samsung CRT TVs - Functional composition of Samsung CRT TVs.
Composition of Samsung LCD TVs - Functional composition of Samsung LCD TVs.
Some useful recommendations for owners who decide to buy a new TV due to the unrepairability of the old one can be found on the page: how to choose a TV when buying.
Comments and suggestions are welcome and welcome!
During the existence of video equipment, several generations of televisions have already been replaced. Each new generation differed not only structurally, but also with a new filling. Nevertheless, many manifestations of defects remained unchanged for all televisions. Knowing the general structure and principle of operation of TVs, a qualified specialist is able to determine the nature of the defect by external manifestations.
Fuses blow when turning on the TV.
Breakdown of one of the diodes of a bridge network rectifier, filter capacitors or a key element (transistor) of a switching power supply.
The TV does not turn on, the supply voltage is not supplied to the modules (the case when they say that the power supply does not start). The fuses are OK.
An open circuit in the voltage supply circuit to the key element, a malfunction of the starting circuit or group stabilization, the absence of a turn-on command signal, a breakdown of the diode of the secondary half-wave rectifier supplying the line scan output stage is also possible.
Vertical line distortion due to erratic lines or woody image noise.
Poor filtering of one or more voltages produced by the switching power supply.
There is no picture and sound on any TV channel. Snow noise appears on the screen.
One of the control voltages is not supplied to the channel selector: tuning voltage, range switching or AGC voltage. A malfunction of the channel selector itself or the first stages of the UPCHI, FSS is possible.
There is no reception of TV programs in the UHF range.
There is no range switch voltage or a malfunction of the channel selector itself.
No sound in normal picture.
The volume control voltage does not come, the speaker is turned off, a malfunction in the UPCHZ or ULF (UZCH) cascades.
The CRT screen does not light up with normal sound. There is no heating of the kinescope, or accelerating or high voltage.
An open circuit in the voltage supply circuit of the kinescope filament. The horizontal output stage does not work due to the absence of either the supply voltage or trigger pulses.
The CRT screen does not light up with normal sound. Kinescope glow, accelerating and high voltage is normal.
The kinescope is locked: the PCTS processing channel (chrominance module) does not receive the voltage for adjusting the contrast or brightness of the image, the PCTS itself, strobe pulses, or instead of personnel blanking pulses, a constant voltage is supplied. There may be a malfunction of the video processor microcircuit or its supply voltage is too low.
The CRT screen glows white. Brightness is maximum and not adjustable. The lines of the reverse motion of the vertical scan are visible. Is there sound.
Open circuit in the kinescope modulator circuit, in the power supply circuit of the output video amplifiers. The reference voltage of the output video amplifiers is underestimated. A malfunction of the video processor chip is also possible.
The CRT screen is “flooded” with one of the primary colors.
Breakdown of one of the output video amplifiers or breakage of its collector load. It is also possible that there is a malfunction in the path of one signal of the main color in the video processor microcircuit or a short circuit of one of the cathodes to the modulator in the kinescope.
One of the primary colors is missing from the image.White balance is out of order.
The signal of the main color does not enter the kinescope cathode due to an open circuit in the circuit of its passage from the output video amplifier, breakage of one of the video amplifier transistors, loss of emission from one of the three kinescope spotlights. There may also be a malfunction in the chain of one signal of the primary color in the video processor microcircuit after the circuits of the second matrixing.
One of the primary colors is missing from the image. White balance is maintained.
One of the color-difference signals is not supplied to the circuits performing the second matrixing, or is not produced by the chrominance decoder.
A color image is reproduced in black and white. Sound is normal.
The signal for adjusting the color saturation is not received, the color television system is not recognized due to the detuning of the parameters of its circuits or filters for extracting color signals from the PCTS. It is also possible that the chrominance decoder chip is malfunctioning or its supply voltage is too low.
A color image (fuzzy) is reproduced with low brightness and unnatural coloration (oversaturated). There is no black and white image.
An open in the luminance signal path (most often an open in the luminance signal delay line).
Noticeable difference in brightness of adjacent lines of a color image. Black and white image is normal.
It is typical for the SECAM system, when color signals with different peaks arrive at the electronic switch or one does not arrive at all, for example, due to a 64μs delay line break.
Open circuit in the PCTS supply circuit to the amplitude selector microcircuit, violation of the operating mode of this microcircuit or its failure.
No line sync.
Detuning of the natural frequency of the horizontal master oscillator, malfunction in the AFC and F circuits of the horizontal master oscillator.
No frame sync.
Detuning of the frequency of natural oscillations of the master oscillator of the vertical sweep, an open or short circuit in the supply circuit of the frame sync pulses.
The image shows the vertical retrace lines.
There are no frame blanking pulses from the frame scan on the PCTS processing circuit (chromaticity module) or the accelerating voltage of the kinescope is greatly overestimated.
There is a thin horizontal stripe instead of an image on the screen.
The supply voltage is not supplied to the output stage of the frame scan, a malfunction of the frame scan itself or an open circuit in the chain of the passage of frame deflecting currents.
The vertical linearity of the image is violated.
The supply voltage of the frame scan is underestimated, the failure of radioelements in the linearity control circuit of the frame scan, including in the negative feedback signal generation circuit.
The size of the image horizontally is small, while the pincushion distortion of the raster is observed.
The supply voltage of the output stage of the horizontal scan is underestimated, an open circuit in the circuit of the transistor that modulates the horizontal deflection currents, or a malfunction in the control circuit of this transistor.
The horizontal image size is too large to be adjusted.
Breakdown of one of the diodes of the diode modulator, breakdown of the transistor that controls the diode modulator.
A thin vertical stripe is visible on the screen.
An open circuit in the line of deflection currents, most often due to violations in the installation.
The mains fuse blows when the TV is turned on.
A malfunction most often occurs due to short circuits in the primary circuits of the power source, which are usually caused by surges in the mains voltage, as well as short circuits of conductors as a result of external pollution and household insects entering the TV.
Possible faulty elements in it: mains noise suppression filter C633 LF600 C634 LF601 C635, rectifier D600, capacitors C601 - C603, key transistor of the IC600 microcircuit.
To find a faulty element, after disconnecting the TV from the mains, disconnect the connectors of the demagnetization loop and speaker CN601 and CN1200. The board is placed in the repair position.Measure the resistance between the terminals of the capacitor C603, having previously discharged it through a resistor with a resistance of 200.500 Ohm with a power of 2 W. The resistance of a good circuit must be at least 10 kOhm. With a lower resistance or a short circuit, to speed up the search for the cause of the malfunction, one of the terminals of the resistor R647 is soldered. Thus, the primary circuit of the power supply is divided into two parts: a filter with a rectifier and a microcircuit. The resistance between the terminals of the capacitor C603 is measured again. If the short circuit still occurs, check the serviceability of the rectifier and filter elements. The most common failures are rectifier diodes D600 and capacitors C601 - C603.
In the event of a malfunction of the capacitors C601, C602, it is temporarily permissible for the TV to work without them.
The malfunction of the C603 capacitor can be easily identified visually by the swelling on the top of its case, the rupture of the safety notch or traces of liquid on the board. Defective diodes are replaced with serviceable similar types with parameters: maximum current not less than 2 A, reverse voltage not less than 400 V.
With a low resistance between the terminals of the capacitor C603, they check the operability of the IC600 microcircuit, in which the key transistor with terminals 1-3 (collector, emitter, base, respectively) most often fails.
When repairing a switching power supply, it must be remembered that a number of its circuits have a galvanic connection with the mains. Therefore, it must be connected via an isolation transformer.
TV does not turn on, mains fuse intact
Troubleshooting begins with measuring the DC voltage across the filter capacitor C603, which should be within 270. 310 V. If it is absent, then sequentially check for the presence of voltages on the line filter and the input of the rectifier bridge. One of the reasons for the lack of voltage may be the failure of one (or both) breaking resistors R631, R642, and this, in turn, may be due to a malfunction of the following elements: C603, D600, IC600, C602, C601.
The defective element is found using an ohmmeter.
If the required voltage is available on the C603 capacitor (270. 310 V), then check its presence on the C608 capacitor. If it is absent, then check the serviceability of the resistor R647 and winding 6 - 8 of the T601 transformer.
Then they check the health of the key transistor of the microcircuit and the presence of a supply voltage (7.7 V) at the pin. 9 microcircuits. If the supply voltage is significantly underestimated or completely absent, check the serviceability of the R600 D601 circuit. The following elements most often fail: R605, Q601, D603, C607 (check by replacement), R606.
Short circuits at the outputs of the secondary rectifiers of the power supply can also lead to the defect in question.
The TV does not switch from standby to working. When you try to switch, the standby indicator goes out for 1.2 s and lights up again
If a visual inspection of the installation does not reveal burnt resistors, swollen capacitor cases, traces of soot near the line transformer, then you need to pay attention to the nature of the sound that accompanies turning on the TV.
If at the same time a characteristic sound from a high voltage surge is heard, this means that trigger pulses are applied to the horizontal output stage. Then it can be assumed that the microcontroller, memory and video processor are in good order, and the faults are contained in the circuits of the TDKS line transformer or frame scan.
It is impossible to make an erroneous conclusion about the serviceability of the TDKS even in the presence of the specified sound, because a breakdown can be in its high-voltage part when an anode voltage appears.
Next, connect the oscilloscope to the protection bus (pin 9 of the CN001 connector of the board A) and turn on the TV. If a voltage of 5 V appears for at least a short time, it means that the microcontroller with a PROT protection signal for some reason blocks the activation of the operating mode. It is necessary to find out from which of the sensors this signal comes. To do this, the sensors are turned off one by one and each time they try to switch the TV to operating mode.First, the protection sensor against a malfunction in the vertical scan circuits is turned off, for which one of the terminals of the D505 zener diode (board D) is soldered. If at the same time a bright horizontal strip appears on the screen, and the PROT voltage drops to zero, then the fault is contained in the vertical scan circuits. It is necessary to ensure that the horizontal stripe is not on the screen for a long time in order to avoid burning through the phosphor of the kinescope.
Then they check for the presence of supply voltages at the pins of the IC500 microcircuit: 15 V at the pin. 2 and -15 V on pin. 4, serviceability of elements D504, R508, the presence of personnel sync pulses on the pin. 5 microcircuits.
After that, it is concluded that it is necessary to replace the IC500 microcircuit.
You can check the serviceability of the vertical scan circuits in another way. Connect the oscilloscope to the frame deflection coils and turn on the TV. If frame pulses with an amplitude of 60 V appear for at least a fraction of a second, it means that the vertical scanning circuits are in good order and the malfunction must be looked for in another section of the circuit. If there are no pulses, then check for the presence of CSI on the pin. 1 IC500, as well as the appearance of the supply voltage of the microcircuit at the moment the TV is turned on.
If, after disconnecting the sensor, the TV turns on, then the fault is in the protection circuits. Check the health of the following elements: Q501 - Q503, D504, D505, D507.
If the voltage on the PROT bus remains at 5 V, turn off the horizontal output stage. To do this, with the vertical scan sensor turned off, a jumper is installed between the base and the emitter of the Q802 transistor, which leads to its closure and disruption of horizontal scan oscillations. If at the same time the voltage on the PROT bus drops to zero, then the TDKS or the kinescope are faulty. The panel is removed from the base of the picture tube and the high-voltage wire is disconnected. Remove the previously installed jumper and turn on the TV. If at the same time the voltage on the PROT bus drops to zero again and a high voltage appears, then the kinescope is faulty, otherwise the TDKS is faulty.
If the voltage of 5 V on the PROT bus remains, then this indicates either the presence of a large current consumption in the circuit of the 135 V voltage source, or a malfunction of the protection transistors Q607, Q602 - Q605 of the power supplies. A faulty transistor is detected with an ohmmeter.
If the voltage on the PROT bus is zero, and the TV does not switch to operating mode, then check the presence of voltage on the pin, 3 IC602 microcircuits, power supply to the IC001 microcontroller, and a RESET signal to its pin. thirty.
The initial reset node (RESET), made on the basis of the IC004 chip of the board A, is operational if, when the TV is turned on, the pin. 4 microcontrollers IC001 hold a potential of 0 V for a short time, and then gradually increase to 5 V. Using an oscilloscope, measure the time during which the voltage on the pin. 4 increases from 0 to 2.4 V. This time must be at least 20 ms. Otherwise, IC004 of board A is faulty.
Check for the presence of a voltage of 5 V (commands to turn on the operating mode) on the pin, 2 microcontrollers IC001, on the collector of the transistor Q4, on the pin. 38 of connector CN001 and based on transistor Q604 of board D,
Check for the presence of pulses with an amplitude of 5 V on the lines of each of the two buses! 2C (pin 48 - 51) of the IC001 microcontroller. If there are no pulses on at least one of the terminals, then most likely one of the microcircuits connected to these buses is faulty. These microcircuits are turned off one by one until a voltage of 5 V appears on the bus. The presence of a positive voltage of 5 V on the bus in the absence of pulses also indicates a malfunction of one of the microcircuits. If a faulty microcircuit is found, it is replaced with a known good one.
A malfunction can occur in the IC002 memory chip due to damaged reset circuits. To eliminate the defect, a jumper is installed between the pin. 9 connectors CN001 and housing. Then the following buttons of the remote control are sequentially pressed: “5”, ”- -“, ”5 ″,“ 9 ”, turning on the TV in standby mode, display (“? ”),“ 5 ”,“ VOL + ”,“ on. TV ”,“ 4 ”,“ 9 ”, and then disconnect the TV from the mains.As soon as the red standby indicator goes out, the TV is turned on again. The image should appear, but if after two or three attempts it is not there, then the memory chip must be replaced, and then the necessary adjustments to the geometry, white balance, AGC level and AFC must be made.
The malfunction may occur due to the failure of the tuner and manifest itself as follows. Immediately after turning on the TV, chaotic horizontal stripes appear on the image, accompanied by a crackling sound in the loudspeaker. Then the image disappears, noise appears on the screen and the TV stops responding to commands.
Switching the TV to standby mode can occur by an overload signal coming from the sensor (resistor R608). To check this fact, measure the voltage at the pin. 3 IC602 chips. If it is more than 0.7 V, then the serviceability of the T803 transformer is checked. To do this, disconnect its pin. 4 from the board and turn on the TV. Appeared on the cont. 1 connector CN1201 135 V supply voltage indicates transformer failure. The characteristic signs of its malfunction are as follows: at the moment of switching to standby mode, a characteristic sound of a high voltage surge is heard, the LED flashes 7 times, and then lights up constantly. There is no voltage on the PROT bus.
If all of the above has not eliminated the defect, then most likely the microcontroller is faulty.
The TV does not switch from standby to working. When you try to switch, the indicator LED works cyclically: several flashes - pause
With such a defect, the number of flashes should be carefully calculated, since it indicates a faulty part of the functional diagram of the TV. The relationship between the number of LED flashes with the address of faulty areas and the reference designation of the microcircuits and devices included in them is shown in Table 4.
The CRT screen does not light up. There is no sound. There is a high voltage at the anode
You can verify the presence of high voltage by touching the back of your hand to the surface of the CRT screen. In the presence of tension, a slight tingling sensation will be felt, accompanied by a soft crackle. The static charge generated in this case can also attract a sheet of paper brought to the screen.
The presence of high voltage indicates the serviceability of line scan devices,
Compound : chassis P1B 03. Processors: M52309SP, SZM-143RV. CD on TA8445K.
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Posts: 10959
MASTER + - the tension is the same on the 7th and 12th legs.
MASTER + - thanks for the fragment, I did not find this (with tension on my legs).
Conder installed tested on E7-22, among the new there were
bad. I'll check later, the granddaughter is in the way, I'm a grandfather, I'm sitting with him.
master-lomaster - I will measure it a little later, thanks.
master lomaster - tension on the legs:
1 – 7.9
2 – 0.1
3 – 1.0
4 – 0
5 – 3.0
6 – 2.9
7 – 24.1
8 – 0.3
9 – 0.8
10 – 0
11 – 0.4
12 – 23.8
Yes! On some legs there is a wide spread. How to be?
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Posts: 10532
Yes, and search rules! https://my.housecope.com/wp-content/uploads/ext/2255/forum/viewtopic.php?t=81794&highlight=ta8445.
What about a sweet couple? And then we will complete the repair!
https://my.housecope.com/wp-content/uploads/ext/2255/forum/viewtopic.php?t=59362&highlight=5373zr
What am I kind today!
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Posts: 10959
Leha - Have you tried searching? https://my.housecope.com/wp-content/uploads/ext/2255/forum/samsung-chassis-p1b-download-10027.html
Probovap - there is only one page on this link (maybe I did something wrong).
The problem was solved - I could not see a break in the track from the C407 to the 8th leg under the mask.
Many THANKS to everyone for such quick answers. On the forum I asked the question for the first time.
Where is the green button to mark the solution to the problem. The granddaughter hangs on her ears.
===== You must not think and don’t even have to think that the time will come when it will be easier. V.S. Chernomyrdin ========
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There can be many malfunctions with a Samsung television receiver, and it is not always necessary to have qualified help from a wizard to eliminate them. For example, if the Samsung TV does not turn on, then in some cases it is still possible to repair it with your own hands.
To search for breakdowns in any household appliance, there is a certain sequence of searching for problems. The repair of Samsung TVs is no exception, for which the search for possible breakdowns begins from the outlet and continues in the power supply.Next, the switching board and processor module, sweep and synchronization module, etc. are examined. The study may end in the control unit, troubleshooting the stabilizer or finding a failed transistor in the line scan module. Find it all, without opening the TV set - it is impossible, and the ordinary owner of the device will not be able to fix such a problem.
If the TV is fresh from the store, the chances are very low that it is defective. The reason may be your inattention, and you did something wrong. It is recommended to read carefully instructions for the device... But if he was already in work and suddenly stopped responding when trying to turn it on, then looking for the cause of the failure according to certain signs will help to decide whether to contact the service or you can handle it yourself.
Very often, the owners of TV sets panic and start calling the master at the slightest problem with their device. But if you calm down and take a sober look at the situation, then there may not be a breakdown in equipment. It is required to check the behavior of the TV set for some symptoms.
You want to check what mode the TV is in. For instance, Standby mode - this is the standby mode of the TV, and you can find out about its on state by looking at whether the red light on the unit panel is on. It should be remembered that it is not recommended to leave the television receiver in this mode for a long period of time, since when the unit seems to be turned off, all the circuits of the power supply remain energized. If the power supply occurs power surge, then all primary circuits will burn out, after which the TV receiver will refuse to turn on. Therefore, the unit should be turned off with a button located on its panel in order to reduce the risk of burnout of the electronics.
In the case when you observe the indication, but the TV set does not respond to commands from the remote control, then you can try to turn on the device using control panellocated on it. If you succeed, then the remote control is faulty. Although, in principle, it cannot break, except that a quartz resonator can break from a fall, which will have to be replaced. Most often, in the remote control batteries run out or run out... In any case, it is worth disassembling the remote control and trying to fix the malfunction of the remote control with your own hands.
In a situation where there is no indication, and when you press the button, nothing happens, you do not hear clicks and do not notice the blinking of the LED, then we can assume that defective socket... Of course, you can try to connect the device to another power source, but if this does not help, then, without special knowledge and qualifications, you will not be able to repair the TV receiver with your own hands. Even replacing a conventional fuse will be difficult for you, as they are not easy to find on modern TVs. Therefore, calling the wizard will be the right decision.
If a single blinking of the indicator was noticed, after which it continues to burn with a steady light, or its color has changed, this may mean that the device is in operating mode: either AV or in the mode of connecting to a PC. Therefore, it will be necessary to transfer the unit to TV reception mode... In addition, the TV can be locked against unauthorized use (for example, by children) - in this case, you need to remove the lock using the instructions for the technician.
Please note: if the antenna is not connected to the TV receiver, the TV signal is very weak or is absent at all, then the TV set, after suppressing the noise, may enter the monitor mode. That is, you will see a black screen with no sound.
Everything that a non-specialist in teletechnics can do is limited to checking the elements outside the apparatus. In other cases, it is not recommended to open the device with your own hands, and you cannot do without a wizard.
If it was not possible to turn on the TV from the control panel, then you need to observe the behavior of the standby indicator (it normally lights up with a steady light, more often - red).If it turns off when you try to press the button, then the problem should be looked deeper in the device, as this indicates internal blocking triggered (not to be confused with the child lock, which is activated by the user). This happens when one of the modules fails. In some TV models, a clicking sound can be heard when the lock is activated. You will not be able to fix such a breakdown with your own hands. The only reasonable way out is to call a specialist.
Such color switching indicates that the CPU generated a signal to turn on the device, and it was sent to all modules to execute it. If any the module is out of order, then he cannot execute the command. For example, a failure in the power supply does not allow it to go into the desired mode. In this case, the processor, not receiving confirmation from the power supply unit about normal operation, gives a signal to cancel turning on the TV receiver and returns it to sleep mode.
Such flashing can continue for a long time until the main cause of the failure is removed: the inverter was repaired, the transistor was replaced (for example, on the s62 chassis), the power supply was moved, or another of a large number of reasons.
When the indicator is green, and the TV receiver does not even think to turn on, then this situation can be called ambiguous. Required main board check with the measurement of the voltage supplied to it. Also, a study of commands for launch, backlight, etc. is carried out.
If the lamp turns on, signaling the operating state, but there are no signals from the main board, while the device does not respond to the remote control and pressing the buttons on the case, then this may indicate glitch in software... Only flashing and updating the software will be able to return the normal operation of the motherboard.
This behavior of the indicator indicates that a malfunction has occurred in the TV set, and it does not carry any more useful information. Would need complete electronics diagnostics, starting with the “ringing out” of the power supply and ending with the converters located on the system board.
When it takes a long time to turn on the TV set, this indicates that some unit of the unit is out of order. For TVs with picture tubes and LCD panels, the breakdown factors can be very different. It is quite difficult to identify a malfunction without the necessary experience and knowledge. Since the problem unit still starts to work, and only a qualified technician can get to the bottom of the cause of the failure, using special equipment to carry out the necessary measurements. In some cases, it will be necessary to check the device at the service center at the stand, using special software.
As you can see from the above possible reasons why the TV stopped turning on, there are not so many options for repairing it on our own. This rule also applies to the case when the TV itself turns on and off immediately. And since the unit is a complex electronic device, it requires accuracy during operation and timely service.
221.) SAMSUNG CS-777PTR 72 cm. 8 years diagonal. The sound appears immediately and the image appears after 50 minutes. With an increase in the accelerating voltage, the screen turns gray with reverse lines, but the image does not appear. I unsoldered the cathodes from the circuit so that they hung in the air and measured the voltage at the cathodes with a digital multimeter with the TV turned on R = 176 B = 177 G = 157 Low emission in the green channel. To trick the ABB system, I connected a chain of 6800 pF * 1000V capacitor connected in series and a 300 kΩ resistor between the green cathode and ground on the CRT board. The TV started to turn on normally. If you just connect a resistance of 300 kOhm, then the image does not appear. For December, there are already 2 such TVs and both villages have a green cannon.
222.) Samsung CK5081 chassis P69-SA1-S Fault: IC801 STR-S6707 periodically breaks through. Defective C807 2200pfx1.6kv.
223.) Samsung-CK5035T (chassis-P69SA) Fault: L802 periodically burns out. Defective C812 - periodic breakage of the output of the plate.
224.) SAMSUNG CK-5341TBR. Interchangeability of microprocessors SIM-135-2C69529Y to SIM-135-2AC69539Y.
226.) SAMSUNG CK-6202WTR (chassis SCT-12B). Fault: backtrack at the top of the raster. Testing the capacitors did not bring any result. R307 10 Ohm turned out to be in the cliff.
227.) Samsung CK-5373Z Fault: after replacing the next “sweet couple” SMR + HIS, an image appeared with reverse lines at the top of the screen. Replace C407 (100mkf-35v).
228) Samsung chassis P1B Fault: periodically breaks the image (frames and lines). The defect is similar to the 3USTST when a 470-ohm trimming resistor is cut off in the radio channel at the video signal output. The defect consisted in the drying out of the C252 electrolyte in the video processor circuit (39 feet), a video signal goes through it.
229.) Samsung CK-20R1VR. Fault: after 10-15 minutes. after switching on the image “blurred” - focusing worsened, brightness dropped. By adjusting the SCREEN it was possible to slightly correct the picture. Suspicion fell on TDKS, but after its replacement, nothing changed. The reason turned out to be in the tube of the picture tube, after disassembling it, it was found that the output of the panel, corresponding to the accelerating electrode, was “stitched” over the plastic to the “common” one.
230.) SAMSUNG CS-15K2M, chassis KS9A Fault: the TV does not turn on from standby mode, when you try to turn on, the LED goes out for a second and immediately lights up again, after which the TV no longer responds to the remote control or buttons until you turn it off its network button. After a lengthy diagnosis, it turned out that the power supply + 3.3v sank a little, instead of what it was supposed to be + 3.2v, this turned out to be enough for the TV to stop turning on, 0.1 volt was added by the protective zener diode of this power supply DZ806, although it called as a serviceable one. The suspicion of a large current consumption by + 3.3V power supply became, when I measured the modes of the IC802 KA7632 microcircuit, it had about + 4.5V on its first leg instead of + 9.0V, and the R824 33Ohm resistor was very hot, with this legs and a voltage of + 3.3v is made, although the microcircuit itself did not warm up.
231.) SAMSUNG CK-2139VR. Fault: the power supply unit gives out underestimated voltages. Instead of 123v-60v, instead of 13v-5v. In the secondary circuits of the power supply, a controlled zener diode 431LZ was replaced. The power supply is assembled on 5Q0765RT.
232.) SAMSUNG CK-5079ZR Fault: according to the owner, periodically, after two weeks, it was necessary to adjust the tuning to the channels. After a couple of months, it became impossible to tune the TV. Reason: a gradual increase in the resistance of the resistor R928 10k from the + 31V zener diode to the transistor that regulates the tuning voltage of the tuner.
233.) Once again about SMR40200 and HIS0169. Ten year old Samsung. Fault: the line transistor is “killed”. There is almost 200V in the duty room, but the R2K protective diode is still alive. Since the old SMR is still in a black case, I decide to change the “sweet couple” to “green” by age. The new kit also delivers the same 200V! Everything squeals on the old TV. The problem was solved by replacing the legendary 22.0x35 capacitor, which is near the microassemblies, by 100.0x50. Everything is in the working room 127.5, in the duty room 139. And yet - it has been checked many times - sometimes it really helps to replace the choke or install 130 ohms in series with it, but, alas, not always.
234.) When repairing another Samsung with a power supply on a couple of SMR42000 HISO169, I bought a green SMR. At the moment of the start, the “greens” emitted a hiss and went into a breakdown. Frustrated, I measure a field worker (SSH7N60A) - not broken. In the section "fuflyandiya" I find messages about the left "greenery", the photo is exactly like mine. And then I smelled the smell of burnt plastic from the SMR. The field worker decided to knock off the SMR and found on it a trace of an arc breakdown from the drain platform on the plastic onto the fastening screw! I fixed the pole piece to the radiator using a clamping method, soldered the rest of the SMR separately. It works! The spent 280 rubles still did not go to waste and in general the “greenery” turned out to be of high quality. Standby mode 137 volts.
235.) SAMSUNG CS-21K3Q (chassis: KS1B). There is no raster, there is sound, the channels are switched (by ear), there is heat. All voltages are normal, except for the accelerating one: 0 volts. If the accelerating wire is disconnected from the CRT board, then the voltage on the wire is present, when the CRT is connected to the board, it is 0. The capacitance C508 4700pf 3kv on the CRT board in the accelerating circuit is defective. The composition of the TV: TDA9381PS / N2 / 3I0912, LA7845 (personnel), TDA8944 (sound), D5703 (page transistor), FUH-29A001B (S) (line), TA7632.
236.) SAMSUNG-CS21K2Q. The fault is sound, there is no raster, no heat, secondary voltages from TDKS are greatly underestimated.The FFA61012L transformer itself is hot, and it is the culprit of all the troubles. I could not find my native TDKS, I put FUH29A001B (S). I got up one to one, in the service I put only SCREEN. The transformer was manufactured by ANHUI XINGYE (China). There are errors in the schema attached to the trance. The numbering of the VIDEO and + B pins is incorrect.
237.) Samsung CW5082Z at the age of 12. Fault: does not turn on. A blown fuse. Complete breakdown of the key transistor in m / sh STRS6707. This happened due to the degradation of C814, C808, each 220.0x25V. Replacement for 200MK * 50V. Replacing "to the heap" C815 4.7x160 V by 10.0x250V. Installed STRS6708 instead of STRS6707. Everything worked, the picture tube was surprisingly well preserved.
238.) Samsung CK5038ZR chassis SCT11B Fault: noisy image, as if a drill is working nearby or high sparks. The culprit is PAP101 (PAP102T), which is right after the selector. To check, apply the signal from the output of the IF1 selector to the input of the K3255K filter (SFK01). The capacitor CK01 (0.01 μF) is temporarily disabled.
239.) Samsung 5079ZR. Fault: periodically the picture tube screen “fills” with green color. In this case, reverse lines are visible and the green level can periodically change. When one of the multimeter probes on the CRT board touched the green green contact area of the cathode, the normal operation of the CRT was restored for an unpredictable time in the range from 10 minutes to several hours. The malfunction was eliminated by replacing the video amplifier chip (TDA6103Q).
240.) SAMSUNG CK5339Z Fault: there is a raster, no OSD, a blurry blue-green glow on the screen, and the raster is full. Weak reaction to focusing, with an increase in the accelerating one, a rustle is heard from under the deflecting deflector, a sensation of turn-to-turn breakdown. Replacing the deflecting, result 0, substituted another picture tube, the same result. On U cannons, the rate, the acceleration is adjustable, everything is normal. All chains around the scribe checked, nothing! Replacing the line, the same. When replacing the deflecting one, I drew attention to the fact that the lower part of the base of the tube's neck is heated quite strongly. I turned the OSKU 180 on the pipe, the top of the pipe base is heated. It turned out to be in personnel, TDA8356, 7 leg, output to the coil, shorted to GND. The beam in the tube, deviating, apparently rested against the base of the tube and ricocheted onto the picture tube mask, with prolonged operation of the picture tube, it would come to an end, the tube would surely burst! After replacing ms, everything became normal. Before turning on with a new ms, it is worth looking through all the electrolytes, in this case, the electrolyte has 47 * 25v near the personnel radiator, ESR = 8 ohm, with normal capacity. This was probably the reason for the failure of ms.
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