Technical description and composition of the LG 42LK430 TV, panel type and applicable modules. The composition of the modules.LG
Model: 42LK430
Chassis / Version: LD01U
Panel: LC420WUE (SC) (A2)
T-CON: 6870C-0310C, LC420WUN-SCA1
Inverter (backlight): integrated into PSU
PWM Inverter: BD9270F (24 pin)
Power Supply (PSU): EAX61124201 (16) REV1.3
PWM Power: STR-W6053N, HS01G (PFC)
MainBoard: EAX64272803 (0), EBR74234627, SAA35750021, SAA35739321
IC MainBoard: CPU: LGE2111-E8; SPI Flash: MX25L8006EM;
Tuner: TDSS-G101D
Control: AKB72915244, IR: BM-LDS104 (LD450), EBR64965801
Specifications 42LK430
LG 42LK430
General recommendations for repairing TV LCD
Repair and diagnostics of any electronic device, in particular LG 42LK430, it is advisable to start with a careful external examination of internal and external elements. Many visible changes in the state of the elements make it possible to determine the future direction of the troubleshooting. 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.
If the TV does not turn on, no indicators on its front panel are lit or blinking. Also, if the TV does not respond to the remote control and buttons, does not make any sounds or any signs of operability when turned on, there is a certain chance that the EAX61124201 (16) REV1.3 power module is faulty and needs repair. Sometimes with similar manifestations a problem can only occur in the absence of standby power. First of all, it is necessary to replace the swollen capacitors of the rectifier filters, if any. If the mains fuse is broken in the power supply, in most cases a breakdown of the power key (s) is detected, which can be integrated with the PWM controller, or a separate field-effect transistor can be used. The rectifier bridge diodes and the electrolytic capacitor of the mains rectifier filter should also be checked.
As a rule, the keys in switching power supplies (SMPS) are reliable enough and rarely fail for no reason to be looked for by checking other components of the circuit - electrolytic capacitors, resistors and semiconductor elements of the primary circuit. The PWM chip is verified by replacing it with a known good one.
If when you turn on the LG 42LK430 there is no image, or it appears for a second and disappears completely, but there is sound, most likely either the backlight or the power converter (inverter) are malfunctioning. It is necessary to check the electrolytic capacitors of the filter of the secondary rectifiers in the general power supply unit. All necessary precautions must be observed when disabling the inverter protection during diagnostics and not leaving it disconnected after the repair is completed.
The motherboard EAX64272803 (0), EBR74234627, SAA35750021, SAA35739321 must be checked if there is no reaction to the remote control and function buttons, the standby indicator blinks or lights up constantly. In such cases, if the converters or power regulators of the microcircuit are working, a software update may be necessary. In cases of attempts to repair the MB board (SSB), you need to check the health of its elements - CPU: LGE2111-E8; SPI Flash: MX25L8006EM; which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
Before changing the tuner TDSS-G101D, if there is no possibility of tuning to television channels, you should make sure that there are supply voltages that must be measured at the corresponding terminals of the tuner and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Attention to the owners! Attempts to repair the LG 42LK430 TV independently are not recommended by the manufacturer and can lead to serious negative consequences!
SCHEMATIC DIAGRAM ---------> LG CHASSIS LD01U; MODEL 32LK430, 32LK430A, 32LK430N, 32LK430U, 32LK430/430A/430N/430U-ZA
PSU SCHEMATIC DIAGRAM ---------> LGP42-10LF EAX61124201 EAY60869402 Power supply
The appearance of the MainBoard EAX64272803 is shown in the figure below:EAX64272803
EAX64272803 can be used in TVs:
LG 42LK450-TG (Panel V420H2-L05), LG 32LK430 ZG (Panel LC320WUN (SC)(A2)), LG 42LK430 (Panel LC420WUE (SC)(A2)), LG 42CS560 ZD (Panel LC420WUE (SC)(A3)), LG 32LV3400 ZG (Panel LC320EUN (SD)(V2)), LG 32CS560 (Panel LC320WUN (SC)(A2)), LG 32LK455 32LK455C (Panel EAX64272803).
PSU Advanced
According to the conditions of compliance with modern world standards for household switching power supplies, the EAX61124201 module provides for the use of a Power Factor Correction unit. The PFC circuit is a flyback converter based on the HS01G PWM controller. The reactance of an electrolytic capacitor of a line filter at a frequency of 50-60 Hz is usually not more than 20-30 ohms and its charge directly from the network through open diodes could reach tens of amperes per pulse if no filtering were applied.
As a result of the PFC conversion, an increased voltage on the capacitor (about 380V) cannot directly open the rectifier diodes, on the anode of which the voltage will always be slightly less (about 300V) and then its charging current will always be limited by the elements of the PWM controller. As a result, the envelope of the high-frequency pulses of the consumed current will repeat the shape and phase of the input sinusoidal voltage. The presence of an increased voltage (+ 380V) on the network capacitor indicates the serviceability of the PFC node.
The appearance of the power supply
Main features of the device LG 42LK430:
Installed matrix (LCD panel) LC420WUE (SC) (A2).
The matrix control uses the Timing Controller (T-CON) 6870C-0310C.
To power the backlight, a converter is used, combined with a power supply, controlled by a BD9270F PWM controller (24 pin).
The necessary supply voltages for all nodes of the LG 42LK430 TV are generated by the EAX61124201 power module, or its analogs using STR-W6053N, HS01G (PFC) microcircuits.
MainBoard - the main board (motherboard) is an EAX64272803 module, using CPU chips: LGE2111-E8; SPI Flash: MX25L8006EM; and others.
The TDSS-G101D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC420WUE-SCA2
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1450: 1
Display Colors: 16.7M / 1.06B (8-bit / 8-bit + FRC), CIE1931 72%
Response Time: 5 (G to G)
Frequency: 60Hz
Lamp Type: 16 pcs EEFL Without Driver
Signal Interface: LVDS (2 ch, 8/10-bit), 51 pins
Voltage: 12.0V