Technical description and composition of the LG 43LF590V TV, panel type and modules used. The composition of the modules.LG LED
Model: 43LF590V
Chassis / Version: LD50H
Panel: NC430EUN AACR1
LED backlight: MAK63207801
LED driver (backlight): integrated into PSU
PWM LED driver: BD559
MOSFET LED driver: 5N41
Power Supply (PSU): EAX66171501 (2.1) LGP32D-15CH1
PWM Power: SSC3S111
MOSFET Power: MDF11N65B
MainBoard: EAX66482504 (1.0) EBU63430421
IC MainBoard: CPU: LGE5222, emmc: KLM4G1FEPD-B031, EEPROM: 24C256
Tuner: TDJM-G301D
Specifications 43LF590V
LG 43LF590V
General recommendations for TV LCD LED repair
Possible malfunctions
- LG 43LF590V TV does not turn on at all. Control lamps do not light up or blink. The TV on the remote control and control panel buttons does not respond.
Most often, with similar manifestations, the main power supply module EAX66171501 is faulty. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches (MDF11N65B) and rectifier diodes in the converters for a short circuit.
In case of breakdowns of semiconductors in the secondary circuits, the converter can usually work in an emergency in the short-circuit mode, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse often breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements, which can disable it in key mode, or provoke an excess of the maximum current or voltage values. These can be circuits supplying the PWM controller, damper or frequency setting circuits, or OOS (negative feedback) elements in the stabilization circuit. PWM controllers (PWM) SSC3S111, in the absence of external damage and short circuit between the terminals, are checked by replacing them with known good ones.
- There is no picture, there is sound, all other TV functions are working. When turned on, the image may sometimes appear for a second.
In some of these cases, the malfunction is caused by the lack of display backlighting. Usually the cause of the malfunction is in the breakage of the LEDs, or in the connectors of the LED strips, but sometimes the LED driver is also faulty.
It is impossible to detect an open circuit in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and a voltage of several tens of volts is required to open their junctions. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Usually, Chinese multimeters lightly light one 3-volt LED if you connect the probes to it in the forward direction (red probe to the anode, black to the cathode). For dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of LED health. In the event of a malfunction of the LED, its zener diode will either be cut off or pierced in the K / Z.
- The TV does not go into operation, does not respond to the remote control. The indicator on the front panel is on or blinking.
Repair or diagnostics of the EAX66482504 motherboard should start with checking the stabilizers and power converters required to power the microcircuits and matrix. If necessary, you should update or replace the software (software). In cases of attempts to repair the MB (SSB) board, it is necessary to check the serviceability of its elements - CPU: LGE5222, emmc: KLM4G1FEPD-B031, EEPROM: 24C256 which may require replacement with new ones. If a BGA processor is installed, there is a possibility that the soldering of the contacts of its pins with the board is broken (detected by warming up).
If LG 43LF590V has no picture, but there is sound, often the display backlight of NC430EUN AACR1 simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED driver.
In such cases, you can see a barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the NC430EUN LCD panel - a process that requires experience and qualifications from the technician. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels , If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV you can see light through the holes in the panel case.
In this case, the panel may also be faulty - damage to the strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But the main board MainBoard EAX66482504 often turns out to be faulty, a software failure is also possible.
Then, first of all, it is necessary to check the panel supply voltage, fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within normal limits, it is necessary to trace the passage of LVDS signals from the MainBoard EAX66482504 with an oscilloscope, as well as synchronizing signals to the loops with drivers.
Flooded or unsuccessfully washed screens of LED TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.
If you suspect a malfunction of the TDJM-G301D tuner, first of all, you need to make sure that the software is correct, as well as the presence of the necessary levels of supply voltages and pulses of data exchange with the processor via the I2C bus on the corresponding terminals of the tuner.
Once again, we remind TV users: do not try to repair yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repair to professionals with sufficient experience in the field of electronic repair.
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> CHASSIS : LD50H FOR MODELS 43LF590*, 49LF590* 43/49LF590*-Z*, 43LF590V, 49LF590V
Additional MainBoard RepairMainBoard EAX66482504 is shown in the figure below:
EAX66482504
External view of the power supply
Main features of LG 43LF590V device:
Installed matrix (LED panel) NC430EUN AACR1.
To power the backlight LEDs, a converter combined with a power supply is used, controlled by a BD559 PWM controller. The keys of the 5N41 type are used as power elements of the LED driver.
MainBoard EAX66482504 is shown in the figure below:
EAX66482504
External view of the power supply
Main features of LG 43LF590V device:
Installed matrix (LED panel) NC430EUN AACR1.
To power the backlight LEDs, a converter combined with a power supply is used, controlled by a BD559 PWM controller. The keys of the 5N41 type are used as power elements of the LED driver.
The formation of the necessary supply voltages for all nodes of the LG 43LF590V TV is carried out by the EAX66171501 power module, or its analogs using SSC3S111 microcircuits and MDF11N65B power switches.
MainBoard - the main board (motherboard) is an EAX66482504 module using CPU chips: LGE5222, emmc: KLM4G1FEPD-B031, EEPROM: 24C256 and others.
Tuner TDJM-G301D provides reception of television programs and tuning to channels.
LG 43LF590V TV with LCD NC430EUN AACR1, 43 "(109 cm) 16: 9 format diagonal. This model uses a panel with edge LED backlighting - Edge LED.
The NC430EUN sensor and the MainBoard EAX66482504 software provide viewing of broadcasts and movies in high quality HD at a resolution of 1920x1080 pixels in graphics resolution at 1080p (Full HD).
TV model 43LF590V has built-in SMART software and webOS operating system installed. The connection to the network can be carried out via Wi-Fi wireless connection. The input analog video signal is decoded in PAL, SECAM, NTSC systems. Graphic processing of a digital signal is performed in the 480i, 480p, 576i, 576p, 720p, 1080i, 1080p standards. Supported media file formats: MP3, WMA, MPEG4, HEVC (H.265), DivX, JPEG.
Speaker power of 10 W (2x5 W) is provided by two speakers. The NICAM stereo audio processing system and the Sound Surround function are used.
Communication with other devices via an external interface is supported by standard input and output connectors: antenna input (RF), AV, component, SCART, HDMI x2, USB x2, Ethernet (RJ-45), Wi-Fi, WiDi, Miracast. A headphone jack is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is provided. This interface supports standard resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080.
The digital tuner can receive TV channels in the DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2 standards.