LG LED
Model: 49UB830V
Chassis / Version: LD48V
Panel: LC490EQE (XG) (F2)
LED backlight: 6922L-0128A, 49 V14 ART5 TV REV0.31 R-Type / L-Type 6920L-0001C
LED driver (backlight): integrated into PSU; 74.9V 1.2A (55 inch)
Power Supply (PSU): EAX65613901 (1.6) EAY63149401
PWM Power: ICE3BR4765JZ (Standby DIP-7)
MainBoard: EAX66085703 (1.0) EBT63174502
IC MainBoard: LGE7411 / LGE4331B4, 25L320BE, AT24C256C, H5TQ4G63AFR, NTP7514
Tuner: TDJM-G251D
Specifications 49UB830V
LG 49UB830V
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 49UB830V TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
In such cases, the malfunction should be sought first in the EAX65613901 power module. It is necessary to measure its output voltages and, in case of their absence, check the serviceability of power switches and rectifier diodes in the converters for possible breakdown.
In case of breakdowns of semiconductors in secondary circuits, the converter can usually operate abnormally in short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback (OOS) stabilization circuits. PWM controllers (PWM) ICE3BR4765JZ (Standby DIP-7), if they do not have visible damage to the case and open fault between the terminals, are usually checked by replacement.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
The most likely in these cases is a malfunction of the LED backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To detect a break in the LED lines without disassembling the panel, a current source is required. It is impossible to open transitions connected in series with a simple multimeter; voltage of several tens of volts is necessary.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX66085703 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). In some cases, to repair the MB board (SSB), it may be necessary to replace the chips - LGE7411 / LGE4331B4, 25L320BE, AT24C256C, H5TQ4G63AFR, NTP7514 with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
If there is no reception of television channels, but the TV is working properly from external devices, first of all it is necessary to check the voltage of the tuner TDJM-G251D and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Owners of the 49UB830V TV are recommended for repair only to qualified specialists with the necessary work experience! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!
Service manual / schematic diagram -------------> LG 49UB830V Chassis LD48V.
CHASSIS : LD48V; MODEL : 49UB830V, 49UB830V-ZB/ZG
The appearance of the MainBoard EAX66085703 is shown in the figure below:
EAX66085703
EAX66085703 can be used in TVs:
LG 42UB820V 42UB820V-ZH.ARUWLJU (Panel LC420EQE (PG)(M1)), LG 49UB830V (Panel LC490EQE (XG)(F2)), LG 49UB820V 49UB820V-ZH (Panel LC490EQE (XG)(F2) ), LG 40UB800V 40UB800V-ZA (Panel V400DK1-KE1).
The appearance of the power supply
Main features of the device LG 49UB830V:
Installed matrix (LED-panel) LC490EQE (XG) (F2).
To power the backlight LEDs, a converter is used, combined with a power supply.
The necessary supply voltages for all nodes of the LG 49UB830V TV are generated by the EAX65613901 power module or its analogs using ICE3BR4765JZ (Standby DIP-7) microcircuits.
MainBoard - the main board (motherboard) is an EAX66085703 module, using chips LGE7411 / LGE4331B4, 25L320BE, AT24C256C, H5TQ4G63AFR, NTP7514 and others.
The TDJM-G251D tuner provides TV reception and channel tuning.