Technical description and composition of the LG 43LH500T TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 43LH500T ZA
Chassis / Version: WK: 1603
Panel: TPT430H3 HVN01.U
T-CON: 43T01-C0B T430HVN01.0 CTRL BD
LED driver (backlight): integrated into PSU
PWM LED driver: PF7909S
MOSFET LED driver: AOTF4126
Power Supply (PSU): 715G7574-P01-W03-0H2M
PWM Power: LD7591T, SSC3S121A
MOSFET Power: TK12A60W, AOTF12N65
MainBoard: 715G8003-M01-B00-004K (WK: 1603) EBT64418101
IC MainBoard: CPU: NT72453MBG-LA, NAND: W29N01GVSIAA512
Tuner: TDSY-G430D 394GPASEBIL02G
Specifications 43LH500T
LG 43LH500T
General repair guidelines for TV LCD LED
Possible malfunctions
- The LG 43LH500T TV does not turn on, does not respond to the remote control and the control panel buttons, does not light up or blink indicators.
In such cases, the 715G7574-P01-W03-0H2M power supply is usually faulty. It is necessary to measure its output voltages and, if they are absent, check the power switches (TK12A60W, AOTF12N65) and rectifier diodes for the probability of short circuit in the converters.
In case of breakdowns of diodes in the secondary circuits, the converter can operate in emergency short circuit mode without output voltages, and during short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor at the source of the key usually breaks.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode, or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers LD7591T, SSC3S121A, in the absence of visible damage or explicit short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, but there is sound, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
In such cases, the most likely malfunction of the LED backlight elements. The reason can be both in the power of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
When diagnosing, it is necessary to take into account that it is impossible to check the open in the chain of LED lines without disassembling the panels using a tester or multimeter. To open all PN junctions connected in series, a voltage of the order of several tens of volts is required, and ideally, a current source. By opening the panel, each LED can be checked separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect probes in the forward direction to it. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the 715G8003-M01-B00-004K motherboard should begin by checking the stabilizers and power converters needed to power the microcircuits and matrix. If necessary, update or replace the software (software). In some cases, to repair the MB (SSB) board, it may be necessary to replace the chips - CPU: NT72453MBG-LA, NAND: W29N01GVSIAA512 with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
If there is no reception of television channels, but the TV is working properly from external devices, first of all you need to check the voltage of the TDSY-G430D 394GPASEBIL02G tuner and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
If LG 43LH500T has no picture, but there is sound, often the display backlight TPT430H3 HVN01.U 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 barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the TPT430H3 LCD panel - a process that requires experience and qualifications from the master. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels
If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV you can see light through the holes in the panel case.
In this case, the panel may also be faulty - damage to strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But often the main board MainBoard 715G8003-M01-B00-004K turns out to be faulty, a software failure is also possible.
Then, first of all, you need to check the panel supply voltage, the 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 the normal range, it is necessary to trace the passage of LVDS signals from MainBoard 715G8003-M01-B00-004K with an oscilloscope, as well as synchronization signals to loops with drivers.
Flooded or unsuccessfully washed screens of LED TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.
Attention to users! Self-repair of the LG 43LH500T TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
The appearance of the MainBoard 715G8003-M01-B00-004K is shown in the figure below:715G8003-M01-B00-004K
Main features of the device LG 43LH500T:
Installed matrix (LED panel) TPT430H3 HVN01.U.
The matrix control uses the Timing Controller (T-CON) 43T01-C0B.
To power the backlight LEDs, a converter is used, combined with the power supply, controlled by the PF7909S PWM controller. As power elements of the LED driver, keys of the AOTF4126 type are used.
The necessary supply voltages for all nodes of the LG 43LH500T TV are generated by the 715G7574-P01-W03-0H2M power supply module or its analogs using LD7591T, SSC3S121A microcircuits and TK12A60W, AOTF12N65 type power switches.
MainBoard - the main board (motherboard) is a 715G8003-M01-B00-004K module, using CPU chips: NT72453MBG-LA, NAND: W29N01GVSIAA512 and others.
The TDSY-G430D 394GPASEBIL02G tuner allows you to receive television programs and tune to channels.
LG 43LH500T TV with LCD TPT430H3-HVN01.U, 43 "(109 cm) diagonal, 16: 9 format. The LCD panel implements the principle of direct display backlighting with rear-mounted LEDs - Direct LED.
TPT430H3-HVN01.U matrix and MainBoard 715G8003-M01-B00-004K software provide viewing of broadcasts and movies in high quality HD at a resolution of 1920x1080 pixels in graphics resolution at 1080p (Full HD). Supported media file formats: MP3, MPEG4, JPEG.
Speaker power 10 W (2x5 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
Communication with other devices via an external interface is supported by standard input and output connectors: antenna input (RF), AV, component, SCART, HDMI x2, USB.
The digital tuner can receive television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
The TV uses a 715G7574-P01-W03-0H2M power supply.
Dimensions: With stand 968x618x142 mm, Without stand 968x563x77 mm.
Attention! Panel TPT430H3-HVN01.U LED TV LG 43LH500T is an expensive and unreliable element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.
