Technical description and composition of the LG 42LH3000 TV, panel type and applicable modules. The composition of the modules.LG
Model: 42LH3000 ZA
Chassis / Version: LD91A
Panel: LC420WUE (SB) (C1)
Lamp backlight: 18 Lamp EEFL
T-CON: 6870C-0243C (SB) (C1)
Inverter (backlight): integrated into PSU
PWM Inverter: BD9215F
Trans Inverter: LIF42-001 FLB-2
Power Supply (PSU): EAX55357701 / 32 LGP42-09LF REV 1.3
PWM Power: ICE2PCS06 (PFC), STR-W6252
MOSFET Power: 07N60C3
MainBoard: EAX60686904 (2) EBU60674897
IC MainBoard: CPU: LGE3368A-LF-SF, NAND: FLASH: HY27US08121B-TPCB, SPI FLASH: W25X32VSSIG, EEPROM: M24512
Tuner: TDFW-G235D
Control: IR: YANGWOO 37 42 47 LH30 Ver1.4
Specifications 42LH3000
LG 42LH3000
General recommendations for repairing TV LCD
Possible malfunctions
- LG 42LH3000 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.
With such manifestations, a malfunction is most likely to be detected in the EAX55357701 power supply module. It is necessary to measure the output voltages in its secondary circuits, and if they are completely absent, check the serviceability of the power switches (07N60C3) and rectifier diodes for possible breakdown (short circuit).
In the event of breakdowns in the secondary circuits of the converter, it can usually fail in short circuit mode, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse or current sensor at the source of the key most often breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM ICE2PCS06 (PFC), STR-W6252 chips are usually checked by replacing with new ones, or obviously working.
- 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.
These manifestations can be triggered by a power module, or by defects in the inverter, as well as a distortion of the currents in the lamps due to their uneven wear. If all the electrolytic capacitors of the filter according to the inverter power supply are serviceable, you should make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
Sometimes, for diagnostic purposes, inverter protection must be disabled. In such cases, special care must be taken during work, and the protection circuits should be restored immediately after the repair is completed.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the EAX60686904 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). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the CPU elements: LGE3368A-LF-SF, NAND: FLASH: HY27US08121B-TPCB, SPI FLASH: W25X32VSSIG, EEPROM: M24512. BGA chip malfunctions are usually easy to detect by warming up.
If a TDFW-G235D tuner is suspected of malfunction, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary supply voltage levels and data exchange pulses with the processor via the I2C bus at the corresponding tuner pins.
It should be remembered! Attempts to independently repair the LG 42LH3000 TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
SCHEMATIC DIAGRAM ---------> LG 42LH3010, 42LH3020, 42LH3040 Chassis LD91A
The appearance of the MainBoard EAX60686904 is shown in the figure below:EAX60686904
EAX60686904 can be used in TVs:
LG 32LD320 (Panel T315XW03 V1), LG 32LD320-ZA (Panel T315XW03), LG 32LH4000-ZA (Panel LC320WUN), LG 32LH2000 (Panel LK315T3LA57), LG 32LH2010 (Panel LK315T3LA57), LG 32LF2510 ZB (Panel LC320WUN (SA)(B3)), LG 37LH2000 (Panel LC370WXE (SB)(A1)), LG 19LD320 ZA (Panel M185B1-L02 Rev.C3), LG 26LH2000 (Panel T260XW02 V.R), LG 32LG2100 (Panel LC320WXN), LG 22LH2000 ZA (Panel V216B1-L02), LG 42LH2000 ZA.ARUVLH (Panel LC420WXE (SB)(A1)), LG 32LD321 32LD321-ZB (Panel T315XW03 V1), LG 26LD320 (Panel T260XW04 V.3), LG 19LH2000 19LH2000-ZA (Panel M185B1-L03).
The appearance of the power supply
Main features of the device LG 42LH3000:
Installed matrix (LCD panel) LC420WUE (SB) (C1).
The matrix control uses the Timing Controller (T-CON) 6870C-0243C.
To power the backlight, a converter is used, combined with the power supply, controlled by the BD9215F PWM controller. The transformer LIF42-001 FLB-2 is installed in the inverter converter.
The necessary supply voltages for all nodes of the LG 42LH3000 TV are generated by the EAX55357701 power supply module or its analogs using ICE2PCS06 (PFC), STR-W6252 microcircuits and 07N60C3 type power switches.
MainBoard - the main board (motherboard) is an EAX60686904 module using CPU chips: LGE3368A-LF-SF, NAND: FLASH: HY27US08121B-TPCB, SPI FLASH: W25X32VSSIG, EEPROM: M24512 and others.
The TDFW-G235D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC420WUE-SBC1
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: 1400: 1
Display Colors: 16.7M / 1.06B (8-bit / 8-bit + FRC)
Response Time: 5 (G to G)
Frequency: 60Hz
Lamp Type: 18 pcs EEFL Without Driver
Signal Interface: LVDS (2 ch, 8/10-bit), 51 pins
Voltage: 12.0V