LG LED
Model: 55LB673V ZB
Chassis / Version: LD42B
Panel: LC550DUH (PG) (F1)
LED backlight: 6916L-1629A, 6916L-1741A, 6916L-1630A, 6916L-1743A
LED driver (backlight): integrated into PSU
PWM LED driver: iW7025-00
MOSFET LED driver: 4NQ10L
Power Supply (PSU): EAX65424001 (2.2) LGP55K-14LPB
PWM Power: NCP1034DG, MAP8800 (PFC), ICE3BR4765JZ
MOSFET Power: 13N60M2
MainBoard: EAX65384003 (1.2) EBR78515101
IC MainBoard: CPU: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAIR
Tuner: TDJM-G101D EBL61400501
Control: AKB73756565 & AN-MR500, EBR77970401 YWE3D90000A, WIFI: EAT62093301 TWCM-B001D
Technical Specifications 55LB673V
LG 55LB673V
General repair guidelines for TV LCD LED
Possible malfunctions
- The LG 55LB673V TV does not turn on, does not respond to the remote control and the control panel buttons, and does not blink with any indicators.
With such manifestations, a malfunction is most likely to be detected in the EAX65424001 power supply module. It is necessary to measure the secondary output voltage, and in case of their absence, check the serviceability of the power switches (13N60M2) of the converters and rectifier diodes for a short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during a short circuit in the 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. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power key may be PWM (PWM) NCP1034DG, MAP8800 (PFC), ICE3BR4765JZ. It is checked only by replacement with a known good one.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
In most cases, the malfunction is caused by the lack of a backlight display. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as a health indicator. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- 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 EAX65384003 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: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAIR. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
Before replacing the TDJM-G101D EBL61400501 tuner, if there is no channel setting, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.
Service manual / schematic diagram ------------> LG 55LB673V Chassis LD42B.
MODEL : 55LB67** 55LB67**-Z*
The appearance of the MainBoard EAX65384003 is shown in the figure below:
EAX65384003
EAX65384003 can be used in TVs:
LG 47LB650V ZE (Panel LC470DUH (FG) (P2)), LG 42LB631V ZL (Panel LC420DUH (FG) (A1)), LG 39LB650V (Panel T390HVJ01.2), LG 55LB673V ZB (Panel LC550DUH (PG)(F1)), LG 47LB677V (Panel LC470DUH (FG)(F1)), LG 42LB673V (Panel LC420DUH (PG)(F1)), LG 47LB673V (Panel LC470DUH (PG)(F1)), LG 32LB652V 32LB652V-ZA.BRUWLDU (Panel LC320DUH (FG)(P2)), LG 50LB653V (Panel LC500DUH (FG)(P1)), LG 42LB652V 42LB652V-ZA.BRUWLJU (Panel LC420DUH (FG)(P2)), LG 55LB720V 55LB720V-ZG.BRUWLJU (Panel LC550DUH (PG)(F1)).
The appearance of the power supply
Main features of the device LG 55LB673V:
Installed matrix (LED-panel) LC550DUH (PG) (F1).
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by the iW7025-00 PWM controller. As power elements of the LED driver, keys of the 4NQ10L type are used.
The necessary supply voltages for all nodes of the LG 55LB673V TV are generated by the EAX65424001 power module or its analogs using NCP1034DG, MAP8800 (PFC), ICE3BR4765JZ microcircuits and 13N60M2 type power switches.
MainBoard - the main board (motherboard) is an EAX65384003 module, using CPU chips: LG1311; DRAM: H5TQ4G63AFR-PBC; EEPROM: AT24C256C, EMMC: THGBMAG6A2JBAIR and others.
Tuner TDJM-G101D EBL61400501 provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC550DUH-PGF1
Type: a-Si TFT-LCD, Panel
Diagonal size: 55 inch
Resolution: 1920x1080, FHD
Display Mode: IPS, Normally Black, Transmissive
Active Area: 1209.6x680.4 mm
Surface: Antiglare (Haze 1%), Hard coating (2H)
Brightness: 450 cd / m²
Contrast Ratio: 1400: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 8/10 (Tr / Td)
Frequency: 120Hz
Lamp Type: WLED Without Driver
Signal Interface: EPI, 100 pins
Voltage: 12.0V