Technical description and composition of the PANASONIC TX-42ER250ZZ TV, panel type and modules used. The composition of the modules.PANASONIC LED
Model: TX-42ER250ZZ
Chassis / Version: MSD3463-T8C1
Panel: K420WD8B
LED backlight: K420WD73 A1 4708-K42W73-A1213K01
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3394S
MOSFET LED driver: AOD256
Power Supply (PSU): integrated into MainBoard
PWM Power: OB5269CP
MOSFET Power: AOTF10N65
MainBoard: MSD3463-T8C1
IC MainBoard: CPU: MSD3463-GSA, SPI FLASH: MX25L6406, AUDIO: TPA3110D2
Tuner: SI2151
Control: IR: 4707-43L73F-A1233K11
TX-42ER250ZZ Specifications
PANASONIC TX-42ER250ZZ
General recommendations for TV LCD LED repair
Possible malfunctions
- PANASONIC TX-42ER250ZZ does not turn on, indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
A malfunction in such cases should be looked for primarily in the circuit of a switching power supply (SMPS) - a mains voltage converter (AC / DC), which is combined with the MainBoard MSD3463-T8C1 in this model. Then you should measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of the power switches (AOTF10N65) and the rectifier diodes of the converters for a possible short circuit.
In the event of diode breakdowns in the secondary circuits, the converter can operate in an emergency mode of short circuit without output voltages, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse and / or the current sensor in the source of the key usually breaks off.
Breakdown of Mos-Fet switches used in switching power supplies is often caused by malfunctions of other elements, for example, in the power supply circuit of the PWM controller, in frequency setting or damper circuits, as well as in negative feedback stabilization. PWM microcircuits (PWM) OB5269CP are usually checked by replacing them with new ones, or known to be working properly.
- There is no picture, there is sound, all other TV functions are working. When enabled, the image may sometimes appear for a second.
As a rule, in this case, the backlight of the LED panel is faulty. The reason can sometimes be in the power supply of the LEDs, but more often in their malfunction (breakdown or open circuit), sometimes in the violation of the contact connections of the LED strips.
To identify an open circuit in the LED lines without disassembling the panel, a current source is required. It is impossible to open the junctions connected in series with a simple multimeter; a voltage of several tens of volts is required.
- The indicator blinks or is on constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the MSD3463-T8C1 motherboard should begin with checking the stabilizers and power converters required to power the microcircuits and matrix. If necessary, you should update or replace the software (software). Often the MB (SSB) board needs to be replaced in the event of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - CPU: MSD3463-GSA, SPI FLASH: MX25L6406, AUDIO: TPA3110D2 and replace the failed chips with new ones. Some malfunctions may be associated with the use of BGA soldering technologies in modern Main Board. Usually such defects are detected by local heating of the chip.
If the TV operates normally from external devices, but does not tune to TV channels, the SI2151 tuner may be faulty. In such cases, first of all, you should make sure that there are supply voltages at its corresponding terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the reason for the inoperability of the tuner may be a software failure.
Users and owners of TVs should remember that attempts to repair the PANASONIC TX-42ER250ZZ TV on their own without the appropriate qualifications and the necessary experience can lead to serious negative consequences!
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> MainBoard (Chassis) MSD3463-T8C1
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> PANASONIC TX-42ER250ZZ, Main: MSD3463-T8C1, Panel: K420WD8B
Additional MainBoard RepairTo reduce the backlight current in LED drivers with an MP3394S (MP3394) controller, increase the resistance of the resistor from pin 6 (ISET) to the case. The maximum current in each channel (in milliamperes) for the resistor Rset (in kilo-ohms) is determined from the ratio 790 * 1.23V / (Rset + 0.4).
The appearance of the MainBoard MSD3463-T8C1 is shown in the figure below:
MSD3463-T8C1
MSD3463-T8C1 can be used in TVs:
PHILIPS 32PHT4001/60 (Panel K320WD92), PHILIPS 43PFT4001/60 (Panel K430WD9), TELEFUNKEN TF-LED39S35T2 (Panel K390WD5 K390WD5UB280H200), TELEFUNKEN TF-LED32S35T2 (Panel K320WD5).
The main features of the PANASONIC TX-42ER250ZZ device:
Installed matrix (LED panel) K420WD8B.
To power the backlight LEDs, a converter combined with the MSD3463-T8C1 main board is used, controlled by the MP3394S PWM controller. The keys of the AOD256 type are used as power elements of the LED driver.
The power module is combined with the MainBoard and is made according to the AC / DC flyback voltage converter using OB5269CP microcircuits and AOTF10N65 power switches.
MainBoard - the main board (motherboard) is an MSD3463-T8C1 module, using CPU chips: MSD3463-GSA, SPI FLASH: MX25L6406, AUDIO: TPA3110D2 and others.
The SI2151 tuner provides reception of television programs and tuning to channels.
If the TV malfunctions during operation, you should not forget about the manufacturer's (seller's) warranty obligations, which are indicated in the accompanying documents.
If the PANASONIC TX-42ER250ZZ does not turn on or turns off, it is sometimes useful to check the sockets and extension cords where the TV is connected to the network.
If the PANASONIC TX-42ER250ZZ does not respond to commands from the remote control, but the control buttons on the panel work, there is a high probability of a remote control malfunction (the remote control does not work). It is advisable to check or replace the batteries in it.
If, while watching terrestrial or cable programs, you receive a no-signal (no signal) alert, check the antenna or cable connection.
You can make sure the TV is working from other external signal sources.
If there is no sound when watching analogue TV programs, you should check the sound system for Russia D / K (6.5 MHz), for Europe B / G (5.5 MHz) in the settings. In modern TVs for setting color and sound standards, the region is usually chosen - for "East Europe" (Eastern Europe).
If PANASONIC TX-42ER250ZZ freezes, does not respond to the remote control and control panel buttons, sometimes Reset can help - reboot the processor. To do this, you must disconnect the TV from the network by pulling out the power plug from the outlet, and turn it back on after 15-20 seconds.
TV PANASONIC TX-42ER250ZZ with LCD display K420WD8B, diagonal size 42 "(107 cm) 16: 9 format. The technology of manufacturing the screen of this TV model is realized with LED backlighting.
The K420WD8B panel and MSD3463-T8C1 motherboard firmware provide HD and Full HD viewing at 1920x1080 pixels in 1080p (Full HD) graphics. Multimedia file formats supported by the video processor: MP3, WMA, MPEG4, MKV, JPEG.
The power of the acoustic audio system is 16 W (2x8 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, VGA, HDMI x3, MHL, USB x2. A headphone output is provided for individual listening.
The digital tuner is capable of receiving terrestrial and cable channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Dimensions: with stand 946x602x227 mm, without stand 946x553x76 mm.
TV weight: 7.4 kg.
Attention! Panel K420WD8B LED-TV PANASONIC TX-42ER250ZZ is the most expensive element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.