Technical description and composition of the LG 47LB677V TV, type of panel and applicable modules. The composition of the modules.LG LED
Model: 47LB677V
Chassis / Version: LD42B
Panel: LC470DUH (FG) (F1)
LED driver (backlight): integrated into PSU
PWM LED driver: IW7025-00
Power Supply (PSU): EAX65424001
PWM Power: MAP8800, SSC9527
MainBoard: EAX65384003 (1.2) EBR78599402 // EAX65384004
IC MainBoard: CPU: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAIR
Tuner: EBL61400501 TDJM-G101D
Specifications 47LB677V
LG 47LB677V
General repair guidelines for TV LCD LED
Possible manifestations of defects
- LG 47LB677V does not turn on and does not show any signs of operability. Does not blink indicators and does not respond to any control buttons.
In such cases, the EAX65424001 power supply is usually faulty. It is necessary to measure the secondary output voltage, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for a short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power switch may be PWM (MAP8800, SSC9527). It is checked only by replacement with a known good one.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
Often in such cases, there is no LED backlight. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required. Then it is necessary to open the panel and check each LED separately with a multimeter. If the capabilities of your multimeter do not allow you to open the LED in the forward direction or dual LEd are used, then the PN junction of the emergency zener diode can indirectly serve as a health indicator. In case of LED-a failure, the zener diode PN junction will either be cut off or broken into short-circuit.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX65384003 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). Board repair and replacement of CPU chips: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAIR are manufactured with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
If the TV works normally from external devices, but does not tune into television channels, the EBL61400501 TDJM-G101D tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
Attention! For users and owners of 47LB677V TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-serviceability of the device.
Service manual and schematic diagram ---------------> LG 47LB677V Chassis LD42B.
CHASSIS : LD42B; MODEL : 47LB67**, 47LB67**-Z*, 47LB700V, 47LB700V-ZG
The appearance of the MainBoard EAX65384003 is shown in the figure below:EAX65384003
EAX65384003 can be used in TVs:
LG 47LB650V ZE (Panel LC470DUH (FG) (P2)), LG 42LB631V ZL (Panel LC420DUH (FG) (A1)), LG 39LB650V (Panel T390HVJ01.2), LG 55LB673V ZB (Panel LC550DUH (PG)(F1)), LG 47LB677V (Panel LC470DUH (FG)(F1)), LG 42LB673V (Panel LC420DUH (PG)(F1)), LG 47LB673V (Panel LC470DUH (PG)(F1)), LG 32LB652V 32LB652V-ZA.BRUWLDU (Panel LC320DUH (FG)(P2)), LG 50LB653V (Panel LC500DUH (FG)(P1)), LG 42LB652V 42LB652V-ZA.BRUWLJU (Panel LC420DUH (FG)(P2)), LG 55LB720V 55LB720V-ZG.BRUWLJU (Panel LC550DUH (PG)(F1)).
The appearance of the power supply
Main features of the device LG 47LB677V:
Installed matrix (LED-panel) LC470DUH (FG) (F1).
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by the IW7025-00 PWM controller.
The formation of the necessary supply voltages for all nodes of the LG 47LB677V TV is carried out by the EAX65424001 power module, or its analogs using MAP8800, SSC9527 microcircuits.
MainBoard - the main board (motherboard) is an EAX65384003 module, using CPU chips: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAIR and others.
The tuner EBL61400501 TDJM-G101D provides reception of television programs and tuning to channels.