Technical description and composition of the LG 55LE5500 TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 55LE5500 ZA
Chassis / Version: LB03E
Panel: LC550EUB (SC) (A4)
T-CON: LGE7378A, MAX17113, MAX9668
LED driver (backlight): 6917L-0025A PCLK-D901 3PHGC10003A-R
Power Supply (PSU): LGP4247-10 IOP EAY60908801
MainBoard: EAX61742609 (4) EBU60864321
IC MainBoard: LGE3556C, M24C16, MX25L4005CM2I, TDA19997HL / C1, NTP-7000
Tuner: TDFR-G155D
Technical Specifications 55LE5500
LG 55LE5500
General repair guidelines for TV LCD LED
Possible manifestations of defects
- LG 55LE5500 TV does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
Most often, with such manifestations, the main power module LGP4247-10 is found to be faulty. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches and rectifier diodes in the converters for a short circuit.
In case of breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM), in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
In some of these cases, the malfunction is caused by the lack of a backlight display. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally, a current source. Having disassembled the panel, it is necessary to check each LED separately. Chinese multimeters, as a rule, light up a single 3-volt LED in the forward direction. In the case of using dual 6-volt LEDs, the PN junction of its protective zener diode can serve as a health indicator. In faulty LEDs, the 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 EAX61742609 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). In some cases, to repair the MB (SSB) board, it may be necessary to replace the chips - LGE3556C, M24C16, MX25L4005CM2I, TDA19997HL / C1, NTP-7000 with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
If the TV works normally from external devices, but does not tune into television channels, the TDFR-G155D tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
Attention to users! Self-repair of the LG 55LE5500 TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
Service manual / schematic diagram ------------> LG 55LE5500 Chassis LB03E
The appearance of the MainBoard EAX61742609 is shown in the figure below:EAX61742609
EAX61742609 can be used in TVs:
LG 42LE5500 ZA (Panel LC420EUH (SC)(A1)), LG 47LE5500 ZA (Panel LC470EUH (SC)(A1)).
The appearance of the power supply
Main features of the device LG 55LE5500:
Installed matrix (LED-panel) LC550EUB (SC) (A4).
The matrix control uses the Timing Controller (T-CON) LGE7378A.
The LED driver 6917L-0025A is used to power the backlight LEDs.
The formation of the necessary supply voltages for all nodes of the LG 55LE5500 TV is carried out by the LGP4247-10 power module, or its analogs.
MainBoard - the main board (motherboard) is an EAX61742609 module, using LGE3556C, M24C16, MX25L4005CM2I, TDA19997HL / C1, NTP-7000 and others.
The TDFR-G155D tuner provides television reception and channel tuning.
