Technical description and composition of the LG 42LG5000 TV, panel type and applicable modules. The composition of the modules.LG
Model: 42LG5000
Chassis / Version: LD84D
Panel: T420HW01 V.2
T-CON: T420HW01 V2 Control Board; AS15-F, W9412G2CB-6
Inverter (backlight): Master: VIT71053.50, Slave: VIT71053.51
PWM Inverter: OZ964SN
Power Supply (PSU): EAX40157601 / 17 EAY4050520
PWM Power: NCP1207 (PWM Flyback), SG6961SZ (PFC), NCP1396ADR2G (PWM resonant)
MainBoard: EAX40150702 (3)
IC MainBoard: CPU: LGE7363C-LF, SPI Flash: 25L3205DM2I
Tuner: TDFV-G135D
Specifications 52LG5030
LG 42LG5000
General recommendations for repairing TV LCD
Possible malfunctions
- LG 42LG5000 does not turn on and does not show any signs of performance at all. Does not blink indicators and does not respond to control buttons.
Most often, with such manifestations, the main power supply module EAX40157601 is faulty. 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 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 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 NCP1207 (PWM Flyback), SG6961SZ (PFC), NCP1396ADR2G (PWM resonant), in the absence of visible damage or frank faults between the terminals, are checked by replacing with new or obviously working ones.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
These manifestations can be triggered by a power module, or by defects in the inverter, as well as a distortion of the currents in the lamps due to their uneven wear. If all the electrolytic capacitors of the filter according to the inverter power supply are serviceable, you should make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the EAX40150702 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). Sometimes they require checking or replacing (if necessary) the elements of the MainBoard - CPU: LGE7363C-LF, SPI Flash: 25L3205DM2I. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
The TDFV-G135D 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.
One of the typical defects of the LG 42LG5000 TV can occur in the T420HW01 V.2 panel.Owners and users of the LG 42LG5000 TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!
External manifestations: color distortion in the image as a negative in the image, light tones predominate. Usually in such cases, the AS15-F gamma corrector is faulty. Another indicator of its malfunction is an excessively strong heating, which in practice allows you to do without measuring voltage gradations of gray.
In most cases, replacing the AS15-F solves the problem.
It should be remembered that similar symptoms can cause faults in the column drivers of the panel, which is usually indicated by interference in the form of even vertical stripes on the screen. Then, after replacing the AS15-F, the situation does not change. Drivers are in loops and cannot be replaced. In this case, it is necessary to replace the glass panel.
SCHEMATIC DIAGRAM ---------> LG 42LG5000 Chassis LD84D
The appearance of the MainBoard EAX40150702 is shown in the figure below:EAX40150702
EAX40150702 can be used in TVs:
LG 32LG5000-ZA (Panel V315B1-C07), LG 42LG3000 (Panel LC420WXN (SA)(A1)), LG 32LG3000 (Panel LK315T3LZ94), LG 42LG5000 (Panel T420HW01 V.2).
The appearance of the power supply
Main features of the device LG 42LG5000:
Installed matrix (LCD-panel) T420HW01 V.2.
The matrix control uses the Timing Controller (T-CON) T420HW01.
To power the backlight, the Master: inverter is used, it is controlled by the OZ964SN PWM controller.
The necessary supply voltages for all nodes of the LG 42LG5000 TV are generated by the EAX40157601 power module or its analogs using NCP1207 (PWM Flyback), SG6961SZ (PFC), NCP1396ADR2G (PWM resonant) microcircuits.
MainBoard - the main board (motherboard) is an EAX40150702 module, using CPU chips: LGE7363C-LF, SPI Flash: 25L3205DM2I and others.
The TDFV-G135D tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: AUO
Model: T420HW01 V2
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: AMVA, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1500: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 15/5 (Tr / Td); 6.5 (G to G)
Frequency: 60Hz
Lamp Type: 18 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V