Wednesday 19 February 2020

REPAIR / SERVICING TV LG 32LN541U

Technical description and composition of the LG 32LN541U TV, panel type and applicable modules. The composition of the modules.
LG LED
Model: 32LN541U ZB
Chassis / Version: LD31B
Panel: HC320DXN-VHFP1 - 21XX / HC320DXN-VHFPA - 21XX / LC320DXE-SFR1
LED backlight: OUT POLA2.0 32LN54 REV 1.0 (13.5.9) A / B TYPE SHARP
T-CON: CPWBX5409TP ZB
LED driver (backlight): integrated into PSU; 70.3V 0.4A
PWM LED driver: MAP3202 (MAP3202SIRH)
MOSFET LED driver: FDT86106, AP18N20GH
Power Supply (PSU): EAX64905001 LGP32-13PL1 EAY62810301
PWM Power: SSC1S311A (PWM flyback), NR891D (PWM Step-down 24/12)
MOSFET Power: MDF11N65B
MainBoard: EAX64891306 EBR76922732
IC MainBoard: CPU: LGE2121-MS; DRAM: H5TQ2G630FR; NAND Flash: SAA36254746F VER 03.13.72; SPI Flash: 25Q80; SOUND: STA3808WF
Tuner: TDSQ-G601D (B) EBL61240503
Control: Remote: AKB73715603, IR: EBR75421804-205 EAX65034404 (1.0)
Specifications 32LN541U
LG 32LN541U
General repair guidelines for TV LCD LED
If the LG 32LN541U does not turn on, no control lights on the front panel light up or blink, therefore, there is a very high probability of a malfunction of the EAX64905001 power module. In some cases, only the processor power regulator may be faulty. In the general case, first of all, it is necessary to check the electrolytic capacitors of the secondary rectifier filters and the fuse at the input of the network. If it is broken, then you should check for breakdown of the PN junctions of the rectifier bridge diodes and the key transistor of the converter, which can either be on a separate radiator or integrated with a PWM controller in a common chip. Options are MDF11N65B.
A breakdown of the power switch of the pulse converter is often triggered by other elements, for example, in the stabilization or control circuits of this switch, as well as by the damper elements in its drain and TPI winding.
Sometimes the LG 32LN541U TV does not have an image, but there is sound, or the image appears and immediately disappears. In this case, there is a possibility of a malfunction of the LED driver - power converter for the backlight LEDs of the HC320DXN-VHFP1 - 21XX panel, or an open circuit in the LED circuit is possible. In such cases, first of all, it is necessary to verify the operability of the electrolytic capacitors of the filter by supplying the backlight unit.
The lack of backlight often occurs due to an open circuit in the LED circuit. There is a need for disassembling the panel and checking the LEDs themselves, as well as the same contact connections in the connectors and rations of the terminals.
To check the LED lines for breaks without disassembling the panel, for example, a current source will help. It is impossible to open series-connected PN junctions with a simple multimeter, a voltage of the order of several tens of volts is required.
When trying to repair the motherboard, you should first check the serviceability of linear stabilizers or power converters of microcircuits and, if necessary, update the software (software).
Board repair and replacement of CPU chips: LGE2121-MS; DRAM: H5TQ2G630FR; NAND Flash: SAA36254746F VER 03.13.72; SPI Flash: 25Q80; SOUND: STA3808WF are manufactured with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
If a TDSQ-G601D (B) EBL61240503 tuner is suspected, it is first necessary to verify the correctness of the software, as well as the presence of the required power supply voltage levels and data exchange pulses with the processor via the I2C bus on the corresponding tuner pins.
It should be remembered! Attempts to repair the TV LG 32LN541U, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!


SCHEMATIC MANAUAL --------------------->LG 32LN54**, 32LN54**-Z*, 32LN536*, 32LN536*-Z* Chassis LD31B/LD36B.


PSU SCHEMATIC --------------->  LG LGP32-13PL1, LGP32I-13PL1


 To reduce the backlight current in TVs with the LGP32-13PL1 power supply unit (EAX64905001), you can increase the resistance of the current sensor, which consists of a set of pairs of low-impedance resistors R822-R829, only 4 pairs of 3.9 + 4.3 Ohm.
Having repaired one pair, we increase the nominal value of the sensor by 25%, which proportionally reduces the current in the LEDs from 400 mA to 300 mA



More details on this page



 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 32LN541U:
Installed matrix (LED-panel) HC320DXN-VHFP1 - 21XX / HC320DXN-VHFPA - 21XX / LC320DXE-SFR1.
The matrix control uses the Timing Controller (T-CON) CPWBX5409TP.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by the MAP3202 PWM controller (MAP3202SIRH). As the power elements of the LED driver, keys of the type FDT86106, AP18N20GH are used.
The necessary supply voltages for all nodes of the LG 32LN541U TV are generated by the EAX64905001 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: LGE2121-MS; DRAM: H5TQ2G630FR; NAND Flash: SAA36254746F VER 03.13.72; SPI Flash: 25Q80; SOUND: STA3808WF and others.
Tuner TDSQ-G601D (B) EBL61240503 provides the reception of television programs and tuning to channels.