Saturday, 15 February 2020

REPAIR / SERVICING TV LG 32LA660V

Technical description and composition of the LG 32LA660V TV, panel type and applicable modules. The composition of the modules.
LG LED
Model: 32LA660V
Chassis / Version: LD33B
Panel: LC320EUB (PF) (P1)
LED backlight: 6922L-0074A 32inch V13 ART TV REV 0.6 1 6920L-0001C
LED driver (backlight): 6917L-0132A PPW-LE32TM-O (A) REV0.5
PWM LED driver: BD9470EFV
MOSFET LED driver: SDB5150D
Power Supply (PSU): EAX64907901 (2.4) LGP32-13P
PWM Power: FA5760N, NCP3170A, LM2903
MOSFET Power: 13NM60N, 10NM60N
MainBoard: EAX64797003 (1.2) EBR76823114
IC MainBoard: CPU: LGE2122, NAND: SAA36403538 VER. 3.20.33, H5TQ4G63AFR x 2, H5TQ2G63AFR, NTP7513
Tuner: TSQ-G601D (B) EBL61240503
Control: WIFI: TWFM-B006D
Specifications 32LA660V
LG 32LA660V
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 32LA660V 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.
With such manifestations, a malfunction is most likely to be detected in the EAX64907901 power module. It is necessary to verify the presence of its output voltages and, if they are completely absent, check the power switches (13NM60N, 10NM60N) and rectifier diodes for a probable 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.
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 FA5760N, NCP3170A, LM2903, in the absence of visible damage or open faults between the terminals, are checked by replacing with new ones, or obviously working.
- 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.
As a rule, in such cases there is no display backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
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.
- The TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the EAX64797003 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). In cases of attempts to repair the MB board (SSB), it is necessary to check the health of its elements - CPU: LGE2122, NAND: SAA36403538 VER. 3.20.33, H5TQ4G63AFR x 2, H5TQ2G63AFR, NTP7513 which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
Before changing the tuner TSQ-G601D (B) EBL61240503, if it is not possible to tune to television channels, make sure that there are supply voltages that need to be measured on 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
Once again, remind users! Attempts to self-repair the LG 32LA660V TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!


schematic manual ---------------------> LG CHASSIS LD33B; Model: 32LA660S, 32LA660V, 32LA662V, 32LA667S, 32LA667V, 32LA6678


 To reduce the backlight current in LED drivers with a BD9470EFV controller (TSSOP-B28), it is necessary to proportionally increase the total resistance of the resistors from pin 8 (ISET) to the chassis. The resistance Rset (in kilo-ohms) is selected from the ratio 3000 / Iled, where Iled is the maximum current in each of the six channels in milliamps.

  More details on this page

 The appearance of the MainBoard EAX64797003 is shown in the figure below:
EAX64797003
EAX64797003 can be used in TVs:
LG 42LA620V (Panel LC420DUE (SF)(U1)), LG 32LN570V (Panel LC320DUE (SF)(R1)), LG 50LA644V (Panel LC500EUN (SF)(F1)), LG 47LA660V (Panel LC470EUG (PF)(F1)), LG 47LA621V (Panel LC470DUE (SF)(U1)), LG 42LA644V (Panel LC420EUN (SF)(F2)), LG 39LA620V ZA (Panel T390HVJ01.0), LG 42LA621V ZD (Panel LC420DUE (SF)(U1)), LG 32LA621V ZD (Panel LC320DUE (SF)(U1)), LG 32LN655V (Panel LC320EUB (PF)(M1)), LG 42LA667V (Panel LC420EUH (PF)(P1) ), LG 47LN613V (Panel LC470DUE (SF)(R4)), LG 32LA667V ZB (Panel LC320EUB (PF)(P1)), LG 55LA660V ZA (Panel LC550EUH (PF)(P1)), LG 47LA620V ZA (Panel LC470DUE (SF)(U1)), LG 32LN613V ZB (Panel LC320DUE (SF)(R4)), LG 42LN655V ZB.BRUZLJU (Panel LC420EUH (PF)(M1)), LG 32LA644V ZA (Panel LC320EUN (SF)(F1)), LG 42LN613V (Panel LC420DUE (SF)(R4)), LG 47LA690V ZB (Panel LC47EUH (PF)(P1)), LG 47LA662V (Panel LC470EUG (PF)(F1)), LG 42LA645V 42LA645V-ZC.BRUYLJU (Panel LC420EUN (SF)(F3)), LG 32LA660V (Panel LC320EUB (PF)(P1)), LG 47LA644V 47LA644V-ZA (Panel LC470EUN (SF)(F2)), LG 50LA667S (Panel T500HVD02.1), LG 47LA691V (Panel LC470EUH (PF)(P1)), LG 32LA662V (Panel LC320EUB (PF)(P1)).
The appearance of the power supply
Main features of the device LG 32LA660V:
Installed matrix (LED-panel) LC320EUB (PF) (P1).
To power the backlight LEDs, the 6917L-0132A LED driver is used, controlled by the BD9470EFV PWM controller. As power elements of the LED driver, keys of the SDB5150D type are used.
The necessary supply voltages for all nodes of the LG 32LA660V TV are generated by the EAX64907901 power supply module or its analogs using FA5760N, NCP3170A, LM2903 microchips and 13NM60N, 10NM60N power switches.
MainBoard - the main board (motherboard) is an EAX64797003 module using CPU chips: LGE2122, NAND: SAA36403538 VER. 3.20.33, H5TQ4G63AFR x 2, H5TQ2G63AFR, NTP7513 and others.
The tuner TSQ-G601D (B) EBL61240503 provides the reception of television programs and tuning to channels.