Technical description and composition of the LG 42LD455-ZA TV, panel type and applicable modules. The composition of the modules.LG
Model: 42LD455-ZA
Chassis / Version: LD01B
Panel: LC420WUG (SC) (A1)
Lamp backlight: 16 Lamp EEFL
Inverter (backlight): integrated into PSU
PWM Inverter: BD9270F
Power Supply (PSU): EAX61124201 / 15
PWM Power: STR-W6053N, HS01G (PFC)
MOSFET Power: K13A60D. K3868
MainBoard: EAX63329201 (9)
IC MainBoard: SPI Flash: W25Q80BVSIG; EEPROM: 24C16WP, 24C08W1
Tuner: EBL60721201 TDTJ-S001D
Control: AKB72915207
Specifications 42LD455
LG 42LD455-ZA
General recommendations for repairing TV LCD
Possible malfunctions
- The LG 42LD455-ZA TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or to the remote control.
In some of these cases, the main switching power supply, the EAX61124201 module, is faulty. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of power switches (K13A60D. K3868) of converters and rectifier diodes for the presence of a possible short circuit.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short-circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key are most often cut off.
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 circuits (OOS) of stabilization. PWM controllers (PWM) STR-W6053N, HS01G (PFC), if they do not have visible damage to the case and open fault between the terminals, are usually checked by replacement.
- 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.
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. After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, it is necessary to ring in its converter the power switches for breakdown and the secondary windings of the transformers for an open.
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 TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX63329201 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). Often, the MB (SSB) card needs to be replaced in case of complex faults that are difficult to detect. When trying to repair, you should check its elements - SPI Flash: W25Q80BVSIG; EEPROM: 24C16WP, 24C08W1 and failed chips replace with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board technologies. Typically, such defects are detected by local heating of the chip.
Before changing the tuner EBL60721201 TDTJ-S001D, if it is not possible to tune to television channels, make sure that there are supply voltages that need to be measured at the corresponding terminals of the tuner and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Attention! For users and owners of 42LD455-ZA TVs who do not have the appropriate qualifications, knowledge and experience, we strongly recommend against attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.
schematic diagram ------------> LG 42LD450, 42LD450N 42LD450, 42LD450N-ZA, 42LD455, 42LD458, 42LD455-ZA, 42LD458-ZA, 42LD465, 42LD465N 42LD465, 42LD465N-ZA, 42LD468, 42LD468-ZA Chassis LD01B.
PSU schematic diagram ------------> LGP42-10LF EAX61124201 EAY60869402 Power supply
The appearance of the MainBoard EAX61354204 is shown in the figure below:EAX61354204
EAX61354204 can be used in TVs:
LG 32LD345 (Panel LC320WXE-SCA1), LG 37LD450 (Panel LC370WUG (SC)(A1)), LG 42LD455-ZA (Panel LC420WUG), LG 32LD550 (Panel LK315D3LA57), LG 42LD450 ZA (Panel LC420WUG (SC)(A1)), LG LG32LD350 32LD350 (Panel T315HW04 V.8), LG 42LD420 ZA (Panel LC420WUG (SC)(A1)), LG 37LD420 ZA (Panel T370HW03 V.B), LG 32LD420 ZA (Panel LC320WUG (SC)(A1)), LG 32LD555 ZC (Panel LC320WUG (SC)(A1)), LG 26LD355-ZA (Panel T260XW04 V.3), LG 37LD425 ZA (Panel T370HW03 V.B), LG 32LD425 (Panel LC320WUG (SC)(A1)), LG 32LD340 32LD340-ZA.BRUWLJU (Panel LC320WXE (SC)(A1)).
PSU Advanced
On the 42LD455-ZA TV, the EAX61124201 / 14 REV 1.1 power module is installed using the PFC (Power Factor Correction) scheme acting as an active filter to eliminate the higher harmonic components of the current consumption. The step-up converter based on the HS01G PWM controller does not allow the input rectifier filter's electrolytic capacitor to be connected to the network directly through open diodes when the charge current is determined by its reactance (of the order of 15-30 ohms at a frequency of 50 Hz). As a result of the conversion, the charging current of the capacitor will be determined in such a way that the envelope of the high-frequency pulses of the input current will repeat the phase and shape of the sine wave of the input voltage. The health check of the PFC unit is carried out by measuring the DC voltage on the capacitor of the rectifier network. In operating mode, it should be around 380V, in standby approximately 300V.
The appearance of the power supply
Main features of the device LG 42LD455-ZA:
Installed matrix (LCD panel) LC420WUG (SC) (A1).
To power the backlight, a converter is used, combined with the power supply, controlled by the BD9270F PWM controller.
The necessary supply voltages for all nodes of the LG 42LD455-ZA TV are generated by the EAX61124201 power supply module or its analogs using STR-W6053N, HS01G (PFC) microchips and K13A60D type power switches. K3868.
MainBoard - the main board (motherboard) is an EAX63329201 module using SPI Flash chips: W25Q80BVSIG; EEPROM: 24C16WP, 24C08W1 and others.
The tuner EBL60721201 TDTJ-S001D provides the reception of television programs and tuning to channels.
Information from an alternative source:
LG 42LD455-ZA chassis LD01B
Panel type (matrix): LC420WUG, Main & T-Con: EAX61354204 (0), Processor: SAA34907920 Ver.3.5.7 (sticker next to it, percent under the radiator), SDRAM: K4B1G1646E-HCH9 (x2), Flash: SAA35408803 Ver .3.03.12 (sticker, type of flash itself), EEPROM: 24C16WP, F0513A, NTP-7100, MAX3232C, Tuner: EBL60721201 TDTJ-S001D, Power supply & Inverter: EAX61124201 / 14 REV 1.1, STR-W6053N, HS01G, K13A60D (x2), K3868 (x4)
Remote control: AKB72915207
Additional technical information about the panel:
Brand: LG Display
Model: LC420WUG-SCA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1450: 1
Display Colors: 16.7M / 1.06B (8-bit / 8-bit + FRC), CIE1931 72%
Response Time: 8/10 (Tr / Td)
Frequency: 60Hz
Lamp Type: 16 pcs EEFL Without Driver
Signal Interface: Mini LVDS, 60 pins
Voltage: 12.0V