Technical description and composition of the PANASONIC TX-L42E5 TV, panel type and modules used. The composition of the modules.PANASONIC LED
Model: TX-L42E5 TX-LR42E5
Chassis / Version: LA35
Panel: LC420EUN (SE) (M3)
LED backlight: 6980L-0001C
T-CON: 6870-0401C 32/37/42/47/55 FHD TM120 Ver 0.3
LED driver (backlight): PCLF-D104 A REV 0.7 6917L-0084A
PWM LED driver: SW5516
Power Supply (PSU): TNPA5608 2 P
PWM Power: R2A20133DSP, FA5760N
MainBoard: TNP0993 4 A
IC MainBoard: CPU: 2WS0250, RAM: K4B2G1646C-HQK0, NAND: 29F4G08ABADA, EEPROM: 24C64F, SOUND: D5452A, LAN: RTL8201F
Tuner: ENVS9302D5F
PANASONIC LED
Model: TX-L42E5 TX-L42E5E
Chassis / Version: LA35
Panel: LC420EUN (SE) (M3)
LED backlight: 6980L-0001C
T-CON: 6870-0401C; TPS65198, TPS65178, TL2350EP
LED driver (backlight): 6917L-0084A PCLF-D104 A REV 0.7
PWM LED driver: SW5516
Power Supply (PSU): TNPA5608 2 P
PWM Power: R2A20133D, FA5760N
MOSFET Power: 600V 12A (PFC), STD13NM60N
MainBoard: TNPH0993
IC MainBoard: CPU: 2WS0250, RAM: K4B2G1646C-HQK0, NAND: 29F4G08ABADA, EEPROM: 24C64F, AUDIO: D5452A
Tuner: ENVS9302D5F
TX-L42E5 Specifications
PANASONIC TX-L42E5
General recommendations for TV LCD LED repair
Possible malfunctions
- The PANASONIC TX-L42E5 TV does not turn on. There are no signs of operability. The indicators on the front panel do not light up or blink, the TV does not respond to the remote control and control buttons.
In such cases, you should start looking for a fault in the circuits of the TNPA5608 power supply. Its output voltages should be measured, and if they are absent, check the serviceability of the power switches (600V 12A (PFC), STD13NM60N) of the converters and rectifier diodes for the probability of a short circuit.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in an emergency mode of short circuit without output voltages, and with a short circuit in the elements of the primary circuit, the mains fuse most often breaks off immediately and less often the current sensor in the source of the key.
Mos-Fet power switches used in switching power supplies sometimes fail due to a malfunction of any other elements that can disable it in the key mode, or create an excess of the maximum permissible key parameters. These can be elements supplying a PWM regulator, frequency setting or damper circuits, or elements of negative feedback in the stabilization circuit. PWM controllers R2A20133D, FA5760N, in the absence of visible damage or outright short circuits between the terminals, are checked by replacing them with new ones, or known to be working properly.
- There is no image, there is sound, it reacts to the remote control. Or, immediately after switching on for a second, the image may appear and immediately disappear.
The malfunction in most of such cases is found in the nodes and elements of the LED panel backlight. The reason may 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.
To check the health of the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED separately with a simple Chinese multimeter (powered by 9 volts) in the P-N transition test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black one to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. Serviceability of the PN junction of the Zener diode indirectly indicates the serviceability of the LED-a
- The TV does not go into operation, does not respond to the remote control. The indicator on the front panel is on or blinking.
Repair or diagnostics of the TNPH0993 motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and the matrix. If necessary, you should update or replace the software (software). Repair of the board and replacement of chips CPU: 2WS0250, RAM: K4B2G1646C-HQK0, NAND: 29F4G08ABADA, EEPROM: 24C64F, AUDIO: D5452A are made with the necessary equipment and the corresponding element base. Failures associated with the use of BGA soldering technologies can be localized by warming up.
If you suspect a malfunction of the ENVS9302D5F tuner, first of all, you need to make sure the software is correct, as well as the presence of the required supply voltage levels and pulses of data exchange with the processor via the I2C bus on the corresponding tuner pins.
If the PANASONIC TX-L42E5 has no picture, but there is sound, often the LCD backlight LC420EUN (SE) (M3) simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED driver.
In such cases, you can see a barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the LC420EUN LCD panel, a process that requires experience and qualifications from the technician. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels
If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV you can see light through the holes in the panel case.
In this case, the panel may also be faulty - damage to strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But the main board MainBoard TNP0993 often turns out to be faulty, a software failure is also possible.
Then, first of all, you need to check the panel supply voltage, the fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within the normal range, it is necessary to trace the passage of LVDS signals from the MainBoard TNP0993 with an oscilloscope, as well as synchronizing signals to the loops with drivers.
Flooded or unsuccessfully washed screens of LED TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.
Once again, we remind TV users: do not try to repair yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repairs to professionals with sufficient experience in the field of electronic repair.
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> PANASONIC TX-L42E5 Chassis LA35 for TX-L42E5E, TX-L47E5E
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> , EEPROM PANASONIC TX-L42E5 TX-L42E5E LA35, Main: TNPH0993, Panel: LC420EUN (SE)(M3)
To reduce the backlight current in LED drivers with a SW5516 controller, you need to proportionally increase the total resistance of the resistors connected between pin 28 of SW5516 and the case, for example, by removing one of the resistors
The appearance of MainBoard TNPH0993 is shown in the figure below:TNPH0993
External view of the power supply
The main features of the PANASONIC TX-L42E5 device:
Installed matrix (LED panel) LC420EUN (SE) (M3).
Matrix control uses Timing Controller (T-CON) 6870-0401C ;.
The LED driver 6917L-0084A is used to power the backlight LEDs, it is controlled by the PWM controller SW5516.
The formation of the necessary supply voltages for all nodes of the PANASONIC TX-L42E5 TV is carried out by the TNPA5608 power module, or its analogs using R2A20133D, FA5760N microcircuits and 600V 12A (PFC), STD13NM60N power switches.
MainBoard - the main board (motherboard) is a TNPH0993 module, using chips CPU: 2WS0250, RAM: K4B2G1646C-HQK0, NAND: 29F4G08ABADA, EEPROM: 24C64F, AUDIO: D5452A and others.
Tuner ENVS9302D5F provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC420EUN-SEM3
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 1%), Hard coating (3H)
Brightness: 360 cd / m²
Contrast Ratio: 1400: 1
Display Colors: 16.7M (8-bit), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
TV PANASONIC TX-L42E5 with LCD LC420EUN, diagonal size 42 "(107 cm) 16: 9 format. The technology of manufacturing the screen of this TV model is realized with LED backlighting.
The LC420EUN panel and TNP0993 motherboard firmware provide HD and Full HD viewing at 1920x1080 pixels in 1080p (Full HD) graphics.
The TX-L42E5 TV is equipped with SMART software, built-in applications and the ability to work on the Internet. Internet connection can be made via Wi-Fi wireless connection. The input analog video signal can be processed in PAL, SECAM, NTSC systems. Graphic processing and formation of a digital signal picture occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Multimedia file formats supported by the video processor: MP3, WMA, MPEG4, DivX, MKV, JPEG.
The power of the acoustic audio system is 20 W (2x10 W) provided by two speakers. Uses NICAM stereo signal system and Sound Surround function.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, SCART, RGB, VGA, HDMI x4, USB x2, Ethernet (RJ-45). A headphone output is provided for individual listening. To connect a computer or laptop, a VGA (D-Sub 15) connector is used that supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768.
The digital tuner is capable of receiving terrestrial and cable channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
The power consumed by the TV in operating mode from the mains is 86 W.
Dimensions: with stand 997x650x247 mm, without stand 997x604x52 mm.
TV weight: with stand: 17 kg, without stand: 14 kg.
Attention! The LC420EUN (SE) (M3) panel of the PANASONIC TX-L42E5 LED TV is the most expensive item.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
Liquid spillage on the screen is unsafe. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.
