Technical description and composition of the LG 42LA615V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 42LA615V
Chassis / Version: LD31B
Panel: LC420DUE (SF) (U2)
LED backlight: 6916L-1214A, 6916L-1215A, 6916L-1216A, 6916L-1217A
T-CON: LC500DUE-SFR1
LED driver (backlight): integrated into PSU; 157V 341mA
PWM LED driver: MAP3202
MOSFET LED driver: FDT86106, STF10NM60N
Power Supply (PSU): EAX64905301 (2.3)
PWM Power: SSC1S311A (PWM flyback), NR891D (PWM Step-down 24/12)
MOSFET Power: MDF11N65B
MainBoard: EAX64891306 (1.1)
IC MainBoard: Cpu: ENGINE LGE2121-MS Spi Flash: MXIC MX 25L8006B, Eeprom: 4256BRP (24C256)
Tuner: TDSQ-G601D (B)
Control: IR: EBR77031901
Specifications 42LA615V
LG 42LA615V
General repair guidelines for TV LCD LED
Repair of the LG 42LA615V TV should begin with a fault diagnosis, which involves a careful inspection of the external and internal elements of the device. Sometimes, based on visible changes in the components of the device, it is possible to draw some conclusions and determine the direction of further troubleshooting even before the necessary measurements are taken. In some cases, faulty elements can be seen with the naked eye, for example, charred resistors or swollen metal-ceramic capacitors, or electrolytic in rectifier filters. Ring cracks formed in the soldered terminals of transformers or heating elements of the circuit are also frequent sources of many malfunctions with a variety of external manifestations.
Sometimes the LG 42LA615V TV just does not turn on. No control lights on the front panel are lit or blinking, the TV does not respond to the remote control and does not make any sounds or any signs of life when turned on. The most likely cause of the malfunction is the failure of the EAX64905301 general power supply module (2.3). If it is working properly, you need to check the processor batteries on the SSB (Main Board). When repairing the power supply, it is advisable to start the diagnostics by checking the mains fuse and the electrolytic capacitors of the filters of the converter secondary rectifiers. In the event of a fuse breaking, the reason should be sought in the power semiconductor elements of the pulse converter of the main power supply. First of all, it is necessary to check the diodes of the bridge of the rectifier of the mains voltage and the power switch (s) of the converter.
If a breakdown of the power switch is detected, it should be remembered that in a switching power supply (IIP) it does not fail by itself without any reasons that should be sought by checking other elements of the primary circuit - electrolytic capacitors, a PWM controller, which can only be checked replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
If the LG 42LA615V does not have an image, but there is sound, the backlight LEDs of the LC420DUE (SF) (U2) panel or their power converter may be malfunctioning. You should also make sure that the electrolytic capacitors of the secondary rectifiers of the common power supply are working.
A malfunction in the backlight circuits often occurs due to an open in the power circuit of the LED lines. It requires disassembling the panel and checking the LEDs themselves, the rations of their terminals, as well as the reliability of the connections in the connectors and rations of the terminals.
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.
Repair or diagnostics of the EAX64891306 motherboard (1.1) should begin by checking the stabilizers or power converters of its microcircuits. If necessary, you should update the software (software).
In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its chips Cpu: ENGINE LGE2121-MS Spi Flash: MXIC MX 25L8006B, Eeprom: 4256BRP (24C256) and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
In cases where there is no tuning to the local television channels, make sure that there are supply voltages at the terminals of the TDSQ-G601D (B) tuner.
We recommend the owners of the 42LA615V TV for repair only to qualified specialists with experience! Self-repair attempts without the appropriate knowledge and skills can lead to serious negative consequences!
Schematic diagram ------------> LG CHASSIS: LD31B; 42LA61XX 42LA6130 42LA6134 42LA6136 42LA613S 42LA613V 42LA615V SERVICE MANUAL,
Schematic diagram PSU ------------> LG 37/39/42 Inch LGP3739-13PL1, LGP42-13PL1
The appearance of the MainBoard EAX64891306 is shown in the figure below:EAX64891306
EAX64891306 can be used in TVs:
LG 32LN540V (Panel LC320DUE (SF)(R1)), LG 42LN542V-ZD (Panel LC420DUE SFR3), LG 32LN541V (Panel LC320DUE (SF)(R1)), LG 42LA615V (Panel LC420DUE (SF)(U2) ), LG 32LA615V (Panel LC320DUE (SF)(U2)), LG 42LN540V (Panel LC420DUE (SF)(R1)), LG 42LN541V (Panel LC420DUE (SF)(R1)), LG 47LN540V (Panel LC470DUE (SF)(R1)), LG 32LB530U ZA (Panel LC320DXE (SG)(R1)), LG 39LN540V (Panel HC390DUN-VCFP1-11XX), LG 32LA643V (Panel LC320EUN (SF)(F1)), LG 32LN542V (Panel LC320DUE SF R1), LG 47LA615V (Panel LC470DUE (SF)(U2)), LG 47LA643V ZB (Panel LC470EUN (SF)(F2)), LG 32LN541U ZB (Panel HC320DXN-VHFP1 - 21XX / HC320DXN-VHFPA - 21XX), LG 32LN536U (Panel NC320DXN (SA)(P1)), LG 37LN541U (Panel LC370DXE (SF)(R1)).
The appearance of the power supply
Main features of the device LG 42LA615V:
Installed matrix (LED-panel) LC420DUE (SF) (U2).
The matrix control uses the Timing Controller (T-CON) LC500DUE-SFR1.
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by the MAP3202 PWM controller. As the power elements of the LED driver, keys of the type FDT86106, STF10NM60N are used.
The necessary supply voltages for all nodes of the LG 42LA615V TV are generated by the EAX64905301 power module or its analogs using SSC1S311A (PWM flyback), NR891D (PWM Step-down 24/12) microcircuits and MDF11N65B type power switches.
MainBoard - the main board (motherboard) is an EAX64891306 module, using Cpu chips: ENGINE LGE2121-MS Spi Flash: MXIC MX 25L8006B, Eeprom: 4256BRP (24C256) and others.
The TDSQ-G601D (B) tuner allows you to receive television programs and tune to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC420DUE-SFU2
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: IPS, Normally Black, Transmissive
Active Area: 927.94x521.96 mm
Surface: Antiglare (Haze 1%), Hard coating (2H)
Brightness: 300 cd / m²
Contrast Ratio: 1200: 1
Display Colors: 16.7M (8-bit), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: WLED Without Driver
Signal Interface: LVDS (2 ch, 10-bit), 51 pins
Voltage: 12.0V