Technical description and composition of the LG 42LB671V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 42LB671V ZF
Chassis / Version: LD42B
Panel: LC420DUH (PG) (F1)
LED backlight: 6916L-1682A, 6916L-1683A, 6916L-1684A, 6916L-1685A; 42 ”V14 Slim DRT REV0.6 1
LED driver (backlight): integrated into PSU
Power Supply (PSU): EAX65424001 (2.3) REV2.0 LGP42-14LP
PWM Power: MAP8800 (PFC), ICE3BR4765JZ (Standby DIP-7)
MainBoard: EAX65384004 (1.5)
IC MainBoard: CPU: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAI
Tuner: EBL61400501 TDJM-G101D
Control: WiFi: 2703H-LGSBW41, BEJLGSBW41, EAT62093301
Specifications 42LB671V
LG 42LB671V
General repair guidelines for TV LCD LED
TV LG 42LB671V ZF, like many other electronic devices, it is advisable to start repairing by inspecting all external and internal elements. Visible damage to elements can sometimes indicate the direction of the search for a defect even before the necessary measurements are taken. In most cases, the repairman can guess the causes of the defect and possible consequences by the characteristic signs of typical TV defects, for example, ring cracks formed in the soldering of the element leads, swollen rectifier filter capacitors, charred resistors and other circuit elements.
Faults in the EAX65424001 (2.3) REV2.0 LGP42-14LP power supply module can be expressed in different ways, for example, LG 42LB671V does not turn on at all and the control lights on its front panel do not light up and do not blink, and there are no signs of operability. After checking the mains fuse and power elements of the primary power supply circuit, it should also check the absence of a short circuit in the loads of the secondary rectifiers.
Mos-Fet keys used in switching power supplies (SMPS) rarely fail for no reason to look for when checking other circuit elements. Often the breakdown is caused by malfunctions of electrolytic capacitors or semiconductor elements in the primary circuit, or by a break in the resistors in the stabilization circuits. The ICE3BR4765JZ PWM controller chip may also cause a breakdown of the power switch of the converter.
If the LG 42LB671V does not have an image, but there is sound and the TV is controlled by the remote control, a malfunction in the backlight circuits of the LC420DUH (PG) (F1) panel is likely. The LEDs or the power converter - LED driver may be faulty. Often in such cases, when you turn on the TV, an image appears and immediately disappears. First of all, it is necessary to verify the operability of the electrolytic capacitors of the rectifier filter supplying the LED driver, and check the LEDs, connecting obviously known good diagnostics.
Often in the absence of backlighting, disassembling the panel is required. It is necessary to check the serviceability of the transitions of the LEDs, as well as the reliability of the contact connections in the rulers and connectors.
To check the LED lines for breaks without disassembling the panel, for example, a current source will help. It is impossible to open series-connected PN junctions with a simple multimeter, a voltage of the order of several tens of volts is required.
Repair or diagnostics of the EAX65384004 (1.5) motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, you should update the software (software).
In some cases, to repair the MB board (SSB), it may be necessary to replace the chips - CPU: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAI for new or obviously working. In cases where BGA technologies are used, defects are usually localized by the heating method.
In the absence of tuning to local television channels, you should make sure that the software is correct, as well as the presence of supply voltages at the terminals of the tuner EBL61400501 TDJM-G101D.
Attention! For users and owners of 42LB671V 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-repairability of the device.
schematic diagram ------------> LG CHASSIS: LD42B MODEL : 42LB67**, 42LB67**-Z*.
User Manual ------------> WiFi LG Wi-Fi Module LGSBW41
The appearance of the MainBoard EAX65384004 is shown in the figure below:EAX65384004
EAX65384004 can be used in TVs:
LG 32LB650V ZE (Panel LC320DUH (FG)(P2)), LG 47LB650V ZE (Panel LC470DUH (FG) (P2)), LG 42LB650V (Panel LC420DUH (FG)(P2)), LG 42LB671V ZF (Panel LC420DUH (PG) (F1)), LG 47LB671V (Panel LC470DUH (PG)(F1)), LG 42LB653V ZK (Panel LC420DUH (FG)(P1)), LG 42LB720V (Panel LC420DUH (PG)(F1)), LG 42LB658V (Panel LC420DUH (FG)(P2)), LG 47LB677V (Panel LC470DUH (FG)(F1)), LG 42LB679V (Panel LC420DUH (PG)(F1)), LG 47LB653V (Panel LC470DUH (FG)(P1)), LG 32LB653V (Panel LC320DUH( FG)(P1)), LG 42LB690V (Panel LC420DUH (PG)(F1)), LG 55LB630V (Panel LC550DUH).
PSU Advanced
The 42LB671V model uses the EAX65424001 power supply unit using the PFC (Power Factor Correction) node - an active filter of the highest harmonics of the current consumption. In fact, this is a boost converter based on the MAP8800 PWM controller, which eliminates the charge current of the electrolytic capacitor of the rectifier filter directly from the network through open diodes, when its charging current is determined by its reactance.
As a result of the operation of the converter, the envelope of the high-frequency pulses of the input current of the converter will repeat the shape and phase of the input voltage. The health of the PFC node can be indirectly judged by the presence of an increased constant voltage (about + 380V) on the capacitor of the rectifier network in operating mode.
The appearance of the power supply
Main features of the device LG 42LB671V:
Installed matrix (LED-panel) LC420DUH (PG) (F1).
To power the backlight LEDs, a converter is used, combined with a power supply.
The necessary supply voltages for all nodes of the LG 42LB671V TV are generated by the EAX65424001 power module or its analogs using MAP8800 (PFC), ICE3BR4765JZ (Standby DIP-7) microcircuits.
MainBoard - the main board (motherboard) is an EAX65384004 module, using CPU chips: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAI and others.
The tuner EBL61400501 TDJM-G101D provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC420DUH-PGF1
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: IPS, Normally Black, Transmissive
Active Area: 927.94x521.96 mm
Surface: Antiglare (Haze 1%), Hard coating (3H)
Brightness: 400 cd / m²
Contrast Ratio: 1400: 1
Display Colors: 1.06B (10-bit), CIE1931 72%
Response Time: 8/10 (Tr / Td)
Frequency: 120Hz
Lamp Type: WLED Without Driver
Signal Interface: EPI, 100 pins
Voltage: 12.0V