Monday 17 February 2020

REPAIR / SERVICING TV LG 32LE5450

Technical description and composition of the LG 32LE5450 TV, panel type and applicable modules. The composition of the modules.
LG LED
Model: 32LE5450 -ZA
Chassis / Version: LD01D
Panel: LC320EUH (SC) (A1)
LED backlight: 3660L-0346A
LED driver (backlight): 3PHAC40003A-R (integrated into PSU)
PWM LED driver: AS3693B, MEGA48PA
Power Supply (PSU): PLDC-L901A EAY60802801
PWM Power: FAN6961 (PFC), L6599D (PWM Resonant), VIPer27L (STB)
MOSFET Power: SD14N60, 04N60C3
MainBoard: EAX61766102 (11)
IC MainBoard: CPU: LGE101DB-LF-T8, SDRAM: K4B1G1646E-HCH9, Flash: W25Q80, EEPROM: 24C1024
Tuner: TDTJ-S001D EBL60721201
Specifications 32LE5450
LG 32LE5450
General repair guidelines for TV LCD LED
Possible malfunctions
- LG 32LE5450 TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
Most likely in this case, the main switching power supply (IIPS) PLDC-L901A is faulty. Then it is necessary to measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches (04N60C3) and rectifier diodes of the converters for the presence of a possible short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during 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. 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) FAN6961 (PFC), L6599D (PWM Resonant), 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, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
Usually in such cases, a malfunction is detected in the backlight nodes of the LED panel. 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.
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. By opening the panel, each LED can be checked separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect probes in the forward direction to it. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX61766102 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). When repairing an MB board, you need to check its CPU components: LGE101DB-LF-T8, SDRAM: K4B1G1646E-HCH9, Flash: W25Q80, EEPROM: 24C1024. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
If the TV works normally from external devices, but does not tune into television channels, the TDTJ-S001D EBL60721201 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.
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 and schematic diagram LG 32LE5450 Chassis LD01D.
43 PAGES YEAR  2010 
MODELS 32LE5300, 32LE5308, 32LE530N, 32LE531C, 32LE5450 -ZA, 32LE5310, 32LE5318 -ZB Chassis: LD01D.

The appearance of the MainBoard EAX61766102 is shown in the figure below:
EAX61766102
EAX61766102 can be used in TVs:
LG 42LE4500 ZA (Panel LC420EUG), LG 42LE4508 ZA (Panel T420HW07 V.5), LG 37LE5300 (Panel LC370EUH (SC)(A1)), LG 32LE4500 ZA (Panel T315HW05 V.3), LG 32LE5300 ZA (Panel T315HW05 V.1), LG 32LE3300 32LE3300-ZA.BRUWLJU (Panel LC320EXN (SC)(A1)), LG 37LE4500 37LE4500-ZA (Panel T370HW04 V.4 ), LG 32LE5450 -ZA (Panel LC320EUH (SC)(A1)).
The appearance of the power supply
Main features of the device LG 32LE5450:
Installed matrix (LED-panel) LC320EUH (SC) (A1).
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by a PWM controller AS3693B, MEGA48PA.
The necessary supply voltages for all nodes of the LG 32LE5450 TV are generated by the PLDC-L901A power module or its analogs using FAN6961 (PFC), L6599D (PWM Resonant), VIPer27L (STB) microcircuits and power switches of the type SD14N60, 04N60C3.
MainBoard - the main board (motherboard) is an EAX61766102 module using CPU chips: LGE101DB-LF-T8, SDRAM: K4B1G1646E-HCH9, Flash: W25Q80, EEPROM: 24C1024 and others.
The TDTJ-S001D EBL60721201 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC320EUH-SCA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 698.4x392.85 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 450 cd / m²
Contrast Ratio: 1300: 1
Display Colors: 1.06B (8-bit + Dithering), CIE1931 72%
Response Time: 8/10 (Tr / Td)
Frequency: 120Hz
Lamp Type: WLED Without Driver
Signal Interface: Mini LVDS, 120 pins
Voltage: 3.3 / 16.0V (VCC / VDD)