Technical description and composition of the LG 32LJ500U TV, panel type and applicable modules. The composition of the modules.
LG LED
Model: 32LJ500U
Chassis / Version: 715G8524
Panel: TPT315B5-WHBN85.K
LED backlight: GJ-2K16 GEMINI-315 D307-V1.1
LED driver (backlight): integrated into PSU
PWM LED driver: 14 pin
MOSFET LED driver: TO-252
Power Supply (PSU): 715G7801-P01-W04-0H2S
PWM Power: SOIC-7pin
MOSFET Power: 6R1K0CE 650V 8A
MainBoard: 715G8524-M01-B00-004T
IC MainBoard: NAND: W29N01GVSIAA
Tuner: TDQS-A751F (L) & TDSY-G430D
Specifications 32LJ500U
LG 32LJ500U
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 32LJ500U TV does not turn on at all. The control lights do not light or flash. The TV on the remote control and the control panel buttons do not respond.
In some of these cases, the main switching power supply - module 715G7801-P01-W04-0H2S is found to be faulty. It is then necessary to measure its output voltages and, if they are absent, you should check the power switches (6R1K0CE 650V 8A) and the rectifier diodes of the converters for a short circuit probability.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the elements of the primary circuit, the mains fuse usually breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback circuits (OOS) of stabilization. SOIC-7pin PWM controllers (PWMs), if they do not have visible damage to the chassis and open short-circuit between the terminals, are usually checked by replacement.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
Often in such cases, there is no LED backlight. The reason can be found in the malfunction of the LEDs, in the violation of the contact connections of the LED strips, or in the provision of their power (LED driver).
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.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
If the LG 32LJ500U has no picture but has sound, often the TPT315B5-WHBN85 display backlight simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED-driver.
In such cases you can see a faintly visible image when external light hits the screen.
To replace the LEDs requires disassembly of the LCD-panel TPT315B5-WHBN85 - the process requiring a master of experience and skill. We do not recommend to perform such works by yourself to owners of TV sets and craftsmen who do not have experience in LCD panel repair.
READ HOW TO REPAIR THE TV LED BACKLIGHT --------------> HERE.
If there is no image, but the backlight works - the screen becomes slightly lighter when you turn on, and in the open TV you can see the light through the holes in the body of the panel.
In this case the panel may be defective - damage to the strips, cables, for example, as a consequence of moisture after an unsuccessful washing of the screen, the T-CON board (Timing Controller) may be defective. But quite often the MainBoard 715G8524-M01-B00-004T is also defective, software failure is also possible.
Then first it is necessary to check the panel power supply voltage, fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within normal limits, you need to trace by oscilloscope the LVDS signals from MainBoard 715G8524-M01-B00-004T, as well as synchronizing signals to driver stubs.
Filled or unsuccessfully washed LED TV screens can be restored in about half of the cases, usually, if there is no significant damage to the panel stubs and slats.
Repair or diagnostics of the 715G8524-M01-B00-004T 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). Board repair and replacement of NAND microcircuits: W29N01GVSIAA are made in the presence of 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.
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 tuner TDQS-A751F (L) & TDSY-G430D. 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, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> FOR 32LJ500U-ZB, 43LJ500V-ZB, 32LJ501U-ZB, 32LJ502U-ZB (EU/CIS) Chassis: NT72461
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> FOR 32LJ500U-ZB, 43LJ500V-ZB, 32LJ503U-ZA, 43LJ503V-ZA, 32LJ503U-ZA, 43LJ503V-ZA(RU) Chassis: NT72461
The appearance of the MainBoard 715G8524-M01-B00-004T is shown in the figure below:
715G8524-M01-B00-004T
The appearance of the power supply
Main features of the device LG 32LJ500U:
Installed matrix (LED panel) TPT315B5-WHBN85.K.
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by a 14 pin PWM controller. As power elements of the LED driver, keys of the TO-252 type are used.
The necessary supply voltages for all nodes of the LG 32LJ500U TV are generated by the 715G7801-P01-W04-0H2S power module, or its analogs using SOIC-7pin microcircuits and 6R1K0CE 650V 8A power switches.
MainBoard - the main board (motherboard) is a module 715G8524-M01-B00-004T, using NAND chips: W29N01GVSIAA and others.
The TDQS-A751F (L) & TDSY-G430D tuner provides TV reception and channel tuning.
There are download files for the 32LJ500U from the manufacturer:
Update and instruction files:
File Description File Name Type Date Size
SW File (Version 3.280) for 32LJ500U-ZB,43LJ500V-ZB,32LJ500V-ZB,32LJ500V-ZB models. Update instructions SW_Download_Guide.pdf PDF 18.07.2018 112K
SW File (Version 3.280) for 32LJ500U-ZB,43LJ500V-ZB,32LJ500V-ZB,32LJ500V-ZB models. Firmware (USB) Software_File(Version_3.280).zip ZIP 18.07.2018 41229K
Compatible with 32LJ500U-ZB, 32LJ500V-ZB, 43LJ500V-ZB.
Instructions and User Manuals:
Document Language Date Size
User Manuals English - English 03.08.2018 12768K
Lithuanian user manuals 03.08.2018 12836K
Latvian, Lettish user manuals 03.08.2018 12833K
You can download the files from the manufacturer's website for the 32LJ500U model.
LG 32LJ500U TV with TPT315B5-WHBN85 LCD screen, measuring 32" (81 cm) diagonally in 16:9 aspect ratio. The LCD-panel implements the principle of direct display backlighting with a rear arrangement of LEDs - Direct LED.
TPT315B5-WHBN85 matrix and MainBoard 715G8524-M01-B00-004T software provide high quality HD image display with 1366x768 pixels resolution in 720p (HD Ready) standard. Supported multimedia file formats are MP3, WMA, MPEG4, DivX, MKV, JPEG.
The speaker system sound power of 10W (2x5W) is provided by two speakers. NICAM STEREO audio processing system is used.
Communication with other devices through an external interface is supported by standard inputs and outputs: antenna input (RF), AV, component, HDMI x2, USB. The digital tuner can receive TV channels in the standards DVB-T, DVB-T2, DVB-C, DVB-S, DVB-S2.
The TV uses a power supply 715G7801-P01-W04-0H2S.
Dimensions: C stand 970x622x219 mm, without stand 728x436x78 mm.
Warning. TPT315B5-WHBN85 LED TV panel is an expensive and fragile part of LG 32LJ500U TV.
Avoid any kind of impact on the glass and pressure on the screen surface to avoid damaging the LED panel!
Also it is not safe to get liquid on the screen. Sometimes one drop is enough if it drips down the glass onto the cables and the TV becomes unrepairable.
