Monday, 2 March 2020

REPAIR / SERVICING TV LG 47LH3000

Technical description and composition of the LG 47LH3000 TV, panel type and applicable modules. The composition of the modules.
LG
Model: 47LH3000
Chassis / Version: LD91A
Panel: LC470WUE
T-CON: LC420_LC470WUN-SBA1 6870C-0243C
Inverter (backlight): integrated into PSU
Power Supply (PSU): EAX56851901 / 29 REV1.3 - LGP47-09L
PWM Power: PWM
MainBoard: EAX60686902 (0) EBR61248510
IC MainBoard: CPU: LGE3368A-LF-SF; RAM: HY5PS1G1631C; SPI FLASH: Winb25X32VSIG; AUDIO: NTP-3100L
Tuner: TDFW-G235D
Control: IR: 37-42-47 LH30 VER1.4
Specifications 47LH3000
LG 47LH3000
General recommendations for repairing TV LCD
TV LG 47LH3000, like many other electronic devices, it is advisable to start repairing by inspecting all external and internal elements. According to some external signs of a change in the state of some elements, it is sometimes possible to make assumptions about the nature of the defect, as well as determine the further direction of the troubleshooting. Useful tips can include swollen capacitors, ring cracks formed in the soldered terminals, a charred paint layer on the resistors, signs of overheating of the board, and many other external signs familiar to experienced repairmen.
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 it is turned on, there is a certain chance that the LGP47-09L - EAX56851901 / 29 REV1.3 power supply module is defective and needs repair. Sometimes with similar manifestations a problem can only occur in the absence of standby power. 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 binding of the IC_Power PWM regulator chip are subject to verification, which it is desirable to verify by replacement.
If the LG 47LH3000 does not have an image, but there is sound and the TV is controlled by the remote control, a malfunction in the display backlight nodes is likely. The lamps or the power converter - inverter 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 inverter, and check the LCD lamps by connecting external and obviously serviceable for diagnosis to the connectors. When disabling the inverter protection (to enable diagnostics), special care must be taken in view of the risk of failure of the power elements. After completing all repair work, it is imperative to restore the protection circuits for full and safe further operation of the TV by the user.
Repair of the motherboard EAX60686902 (0) EBR61248510 should begin with the diagnosis and verification of all linear stabilizers and power converters of its microcircuits. Sometimes it may be necessary to update the software (software) - flashing FLASH or EEPROM. In some cases, to repair the MB board (SSB), it may be necessary to replace the chips - CPU: LGE3368A-LF-SF; RAM: HY5PS1G1631C; SPI FLASH: Winb25X32VSIG; AUDIO: NTP-3100L 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 the channels of on-air or cable television, you should make sure that the software is correct, as well as in accordance with the ratings of the supply voltage at the terminals of the TDFW-G235D tuner. It is also necessary to check the presence of pulses of data exchange between the tuner and the processor via the I2C bus using an oscilloscope.
Once again, remind users! Attempts to self-repair the LG 47LH3000 TV without the appropriate qualifications and experience can lead to its complete non-repairability!


Service manual and schematic diagram -------------->  LG 47LH3000 Chassis LD91A.
CHASSIS : LD91A; MODEL : 47LH3000, 47LH3000-ZA



 The appearance of the MainBoard EAX60686902 is shown in the figure below:
EAX60686902
EAX60686902 can be used in TVs:
LG 37LH3000 (Panel T370HW02 V.G), LG 32LH2000 (Panel LK315T3LA57), LG 32LF2510 ZB (Panel LC320WUN (SA)(B3)), LG 42LF2510 (Panel LC420WUE (SB)(C1)), LG 47LH3000 (Panel LC470WUE), LG 32LH3010 (Panel LC320WUN (SA)(B2)), LG 37LH2010 37LH2010-ZB.BRUVLJU (Panel LC370WXE (SB)(A1)).
The appearance of the power supply
Main features of the device LG 47LH3000:
Installed matrix (LCD panel) LC470WUE.
The matrix control uses the Timing Controller (T-CON) LC420_LC470WUN-SBA1.
To power the backlight, a converter is used, combined with a power supply.
The formation of the necessary supply voltages for all nodes of the LG 47LH3000 TV is carried out by the EAX56851901 power module, or its analogs using PWM chips.
MainBoard - the main board (motherboard) is an EAX60686902 module using CPU chips: LGE3368A-LF-SF; RAM: HY5PS1G1631C; SPI FLASH: Winb25X32VSIG; AUDIO: NTP-3100L and others.
The TDFW-G235D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG.Philips LCD
Model: LC470WUE-SAA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 47 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 1039.68x584.82 mm
Surface: Antiglare (Haze 13%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1200: 1
Display Colors: 16.7M / 1.07B (8-bit / 8-bit + Dithering)
Response Time: 5 (G to G)
Frequency: 60Hz
Lamp Type: 22 pcs CCFL Without Driver
Signal Interface: LVDS (2 ch, 8/10-bit), 51 pins
Voltage: 12.0V