Sunday 23 February 2020

REPAIR / SERVICING TV LG 37LK430

Technical description and composition of the LG 37LK430 TV, panel type and applicable modules. The composition of the modules.
LG
Model: 37LK430
Chassis / Version: LD01U
Panel: LC370WUE
Inverter (backlight): integrated into PSU
Power Supply (PSU): EAX61124201 / 16 REV1.3 3PAGC10011A-R - LGP37-10LA LG3210-LF LG32-10LH LGP32-10LS LGP32-10LA LGP42-10LF
PWM Power: STR-W6053N, HS01G (PFC)
MOSFET Power: 13NM60N, 2SK3868
MainBoard: EAX64290501 (0)
IC MainBoard: CPU: LGE107DC-RP, DDR: H5TQ1G63DFR-PBC, Nand: K9F1G08U0D, FLASH 25Q80
Tuner: TDTJ-S001D
Specifications 37LK430
LG 37LK430
General recommendations for repairing TV LCD
LG with the LD01U chassis, like other TVs, it is advisable to start repairing with a careful inspection of the external and internal elements and modules. In some cases, visible external damage to the elements can suggest the direction of troubleshooting and localization of the defect even before the start of the necessary measurements at the control points of the nodes of electronic circuits. Elements with visible damage, for example, capacitors swelled up after boiling the electrolyte, charred resistors in certain nodes of the circuit, as well as ring cracks in solders will help the master to guess the causes and possible consequences of the malfunction.
In case of a power supply module malfunction, external manifestations may be different, for example, LG 37LK430 does not turn on at all and there is no indication of control lights on the front panel. With the same symptoms, the stabilizer (converter) of the power supply to the control processor may be faulty. Diagnostics and repair of the common power supply should always begin with a check of the mains fuse and the condition of the electrolytic capacitors of the secondary rectifier filters. Defective and swollen capacitors should be replaced with new ones. If the fuse breaks, it is advisable to check for a breakdown, first of all, all the power semiconductor elements of the converter and the diode bridge of the rectifier network, as well as the large electrolytic capacitor of the filter of the rectifier network.
It should be borne in mind that in the practice of repair it is extremely rare that key transistors in switching power supplies (SMPS) fail for no reason that should be sought by checking other components, for example, a breakdown of the key can provoke faulty elements of the damper circuits, or dried electrolytic capacitors or dangling primary resistors BP circuits involved in the stabilization process. In this case, all semiconductor elements of the strapping of the PWM controller chip are subject to verification, which it is desirable to verify by replacement.
If when you turn on the LG 37LK430 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 faulty. It is necessary to check the electrolytic capacitors of the filter of the secondary rectifiers in the general power supply unit. If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
Repair or diagnostics of the EAX64290501 (0) motherboard should begin by checking the stabilizers or power converters of its chips. If necessary, you should update the software (software). Board repair and replacement of CPU chips: LGE107DC-RP, DDR: H5TQ1G63DFR-PBC, Nand: K9F1G08U0D, FLASH 25Q80 are carried out 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.
Attention! For users and owners of 37LK430 TVs who do not have the appropriate qualifications, knowledge and experience, we strongly recommend against attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.


schematic diagram ------------->  LG Chassis LD01U; 37LK430/430A/430N/430U, 37LK430/430A/430N/430U-ZA SERVICE MANUAL.

schematic diagram ------------->  LGP42-10LF EAY60869402 Power supply


 The appearance of the MainBoard EAX64290501 is shown in the figure below:
EAX64290501
EAX64290501 can be used in TVs:
LG 32LV2500-ZA (Panel T315XW06 V.3), LG 37LV3500-ZA (Panel T370HW05 V.1), LG 42LV3400-ZA (Panel T420HW08 V.1), LG 32LK530 (Panel LC320WUD (SC)(A3)), LG 37LK430 (Panel LC370WUE), LG 32LK451 ZA (Panel T315HW04 V.9), LG 42LV3551 (Panel LC420EUN (SD) (V3)), LG 47LW4500 (Panel LC470EUF (SD)(F2)), LG 32LK551 ZB (Panel LC320WUD (SC)(A2)), LG 42LV3500 (Panel LC420EUN (SD)(V3)), LG 42LK551 ZB (Panel V420H2-LH5), LG 42LK451 42LK451-ZG.BRUYLJU (Panel T420HW09 V0), LG 42LK530 (Panel LC420WUF (SC)(A2)), LG 47LK950 ZA (Panel LC470WUF (SD)(P1)), LG 32LW4500 ZB (Panel LC320EUD (SD)(P1)), LG 42LW4500 ZB (Panel LC420EUF (SD)(PX)), LG 42LV4500 DA (Panel LC420EUF (SD)(A1)), LG 32LV4500 (Panel LC320EUD (SD)(A4)), LG 42LV369C (Panel T420HW08 V.9).
PSU Advanced
The 37LK430 TV is equipped with the EAX61124201 / 16 REV1.3 3PAGC10011A-R power module - LGP37-10LA LG3210-LF LG32-10LH LGP32-10LS LGP32-10LA LGP42-10LF using the PFC (Power Factor Correction) circuitry which acts as an active filter to eliminate higher harmonic components of current consumption. The step-up converter based on the HS01G PWM controller does not allow the input rectifier filter's electrolytic capacitor to be connected to the network directly through open diodes when the charge current is determined by its reactance (of the order of 15-30 ohms at a frequency of 50 Hz). As a result of the conversion, the charging current of the capacitor will be determined in such a way that the envelope of the high-frequency pulses of the input current will repeat the phase and shape of the sine wave of the input voltage. The health check of the PFC unit is carried out by measuring the DC voltage on the capacitor of the rectifier network. In operating mode, it should be around 380V, in standby approximately 300V.
The appearance of the power supply
Main features of the device LG 37LK430:
Installed matrix (LCD-panel) LC370WUE.
To power the backlight, a converter is used, combined with a power supply.
The necessary supply voltages for all nodes of the LG 37LK430 TV are generated by the EAX61124201 power supply module or its analogs using STR-W6053N, HS01G (PFC) microcircuits and 13NM60N, 2SK3868 power switches.
MainBoard - the main board (motherboard) is an EAX64290501 module, using CPU chips: LGE107DC-RP, DDR: H5TQ1G63DFR-PBC, Nand: K9F1G08U0D, FLASH 25Q80 and others.
The TDTJ-S001D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC370WUE-SCA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 37 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 819.36x460.89 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1500: 1
Display Colors: 16.7M / 1.06B (8-bit / 8-bit + FRC), CIE1931 72%
Response Time: 10/8 (Tr / Td)
Frequency: 60Hz
Lamp Type: 14 pcs EEFL Without Driver
Signal Interface: LVDS (2 ch, 8/10-bit), 51 pins
Voltage: 12.0V