Technical description and composition of the LG 43UJ639V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 43UJ639V
Chassis / Version: UD74P
Panel: HC430DGG-SLTL2 - 9131
LED backlight: LC43490063A WOOREE 43inch UHD_LED Array A / B-Type
LED driver (backlight): integrated into PSU; 68V 650mA Direct LED
Power Supply (PSU): EAX67209001 (1.5) LGP43DJ-17U1
MainBoard: EAX67133404 (1.0) RS81Q51G6M
IC MainBoard: Realtek K3Lp, FT24C256A, DTA2010M
Tuner: TDJN-G501D
Control: IR: EBR83592703, Wi-Fi: LGSBWAC72 EAT63377302
Specifications 43UJ639V
LG 43UJ639V
General repair guidelines for TV LCD LED
Possible malfunctions
- LG 43UJ639V 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.
Most often, with such manifestations, the main power supply module EAX67209001 is found to be faulty. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of the power switches of the converters and rectifier diodes for the presence of a possible short circuit.
In case of any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And with a short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at the source of the key.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new, or obviously working.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
In such cases, the most likely malfunction of the LED backlight elements. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
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 TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the EAX67133404 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). Often, the MB (SSB) card must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - Realtek K3Lp, FT24C256A, DTA2010M and replace failed chips with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board technologies. Typically, such defects are detected by local heating of the chip.
In the absence of tuning to the channels of on-air or cable television, you should make sure that the software is correct, as well as in accordance with the ratings of the supply voltages on the terminals of the TDJN-G501D tuner. It is also necessary to check the presence of pulses of data exchange between the tuner and the processor via the I2C bus using an oscilloscope.
Attention TV owners! Self-repair attempts by LG 43UJ639V are not recommended by the manufacturer and can lead to serious negative consequences!
Service manual and schematic diagram --------------> LG 43UJ639V Chassis UD74P.
The appearance of the MainBoard EAX67133404 is shown in the figure below:EAX67133404
The appearance of the power supply
Main features of the device LG 43UJ639V:
Installed matrix (LED panel) HC430DGG-SLTL2 - 9131.
To power the backlight LEDs, a converter is used, combined with a power supply.
The formation of the necessary supply voltages for all nodes of the LG 43UJ639V TV is carried out by the EAX67209001 power module, or its analogues.
MainBoard - the main board (motherboard) is an EAX67133404 module, using Realtek K3Lp, FT24C256A, DTA2010M chips, and others.
The TDJN-G501D tuner provides television reception and channel tuning.