Technical description and composition of the LG 47LE8500 TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 47LE8500
Chassis / Version: LD03E
Panel: LE85M47T240V5
LED driver (backlight): integrated into PSU
Power Supply (PSU): LGP4247-10 EAY60908801
MainBoard: EAX61748102 EBR65254204
IC MainBoard: LGE3556C, BD35331F, NT5TU128M8DE, TDA19997
Tuner: TDFD-C055D
Specifications 47LE8500
LG 47LE8500
General repair guidelines for TV LCD LED
Possible malfunctions
- The LG 47LE8500 TV does not turn on, does not respond to the remote control and the control panel buttons, does not light up or blink indicators.
Failure in such cases should begin to be sought in the power supply circuits of the LGP4247-10. It is necessary to measure its output voltages and, if they are absent, to check for short-circuit probabilities in the converters, power switches and rectifier diodes.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more often 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 (OOS) stabilization circuits. PWM controllers (PWM), 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.
A malfunction is usually most likely in these cases at the backlight nodes of the display matrix. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
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 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 EAX61748102 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 LGE3556C, BD35331F, NT5TU128M8DE, TDA19997 microcircuits 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.
The TDFD-C055D tuner malfunction is established after checking the software and all supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be controlled by an oscilloscope.
Once again, remind users! Attempts to self-repair the LG 47LE8500 TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
Service manual and schematic diagram ----------------> LG 47LE8500 Chassis LC03J
The appearance of the MainBoard EAX61748102 is shown in the figure below:EAX61748102
The appearance of the power supply
Main features of the device LG 47LE8500:
Installed matrix (LED panel) LE85M47T240V5.
To power the backlight LEDs, a converter is used, combined with a power supply.
The formation of the necessary supply voltages for all nodes of the LG 47LE8500 TV is carried out by the power module LGP4247-10, or its analogues.
MainBoard - the main board (motherboard) is an EAX61748102 module, using chips LGE3556C, BD35331F, NT5TU128M8DE, TDA19997 and others.
The TDFD-C055D tuner provides television reception and channel tuning.