Technical description and composition of the LG 43LJ519V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 43LJ519V
Chassis / Version: LD76H
Panel: HC430DUN-ABVX2-2144
LED backlight: 43LH51_FHD_A, 43LH51_FHD_B
T-CON: HV430FHB-N1D 47-6021141
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3378E
MOSFET LED driver: AOD2922
Power Supply (PSU): Adapter 19V 3.42A
MainBoard: EAX67041506 (1.2)
IC MainBoard: LGE6351, H27U1G8F
Tuner: TDJA-G501D
Specifications 43LJ519V
LG 43LJ519V
General repair guidelines for TV LCD LED
Possible malfunctions
- LG 43LJ519V does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
In such cases, the adapter power supply is usually faulty.
The external adapter 19V 3.42A power supply is not always subject to repair, especially since the owner can purchase it independently. But, in some cases, it makes sense to open it and eliminate the simple typical defects inherent in converters in pulsed sources. It is necessary to measure its output supply voltages, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for the probability of breakdown in PN semiconductor junctions.
In case of breakdowns of semiconductors in the secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM microcircuits are usually checked by replacement with new ones, or obviously working.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
Often in such cases, there is no LED backlight. The reason can be both in the power of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
To check the health in the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED individually with a simple Chinese multimeter (powered by 9 volts) in the P-N-junction test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. A zener diode PN junction indirectly indicates a LED-a
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the EAX67041506 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the elements LGE6351, H27U1G8F. BGA chip malfunctions are usually easy to detect by warming up.
The TDJA-G501D tuner malfunction is established after checking the software and all supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be controlled by an oscilloscope.
To reduce the backlight current in LED drivers with the MP3378E PWM controller, it is necessary to proportionally increase the total resistance of the resistors from pin 3 (RISET) to the chassis. Calculation of current in milliamperes and resistance in kilo-ohms 977 / Rset for each channel. Parallel channels are summed. For example, for four parallel channels and a RISET 10 KOhm resistance, the total current will be 97.7 * 4 = 391 mA.Attention TV owners! Self-repair attempts by LG 43LJ519V are not recommended by the manufacturer and can lead to serious negative consequences!
The appearance of the MainBoard EAX67041506 is shown in the figure below:EAX67041506
Main features of the device LG 43LJ519V:
Installed matrix (LED-panel) HC430DUN-ABVX2-2144.
The matrix control uses the Timing Controller (T-CON) HV430FHB-N1D.
To power the backlight LEDs, a converter is used, combined with the EAX67041506 main board, controlled by the MP3378E PWM controller. As power elements of the LED driver, keys of the AOD2922 type are used.
To power all the internal components of the LG 43LJ519V TV, an external adapter type 19V 3.42A is used.
MainBoard - the main board (motherboard) is an EAX67041506 module, using LGE6351, H27U1G8F chipsets and others.
The TDJA-G501D tuner provides television reception and channel tuning.