Tuesday, 28 April 2020

REPAIR / SERVICING TV MYSTERY MTV-2224LT2

Technical description and composition of the MYSTERY MTV-2224LT2 TV, type of panel and applicable modules. The composition of the modules.
MYSTERY LED
Model: MTV-2224LT2
Chassis / Version: MSAV3220-ZC26-02
Panel: CLAA215FA10
LED driver (backlight): integrated into Mainboard
Power Supply (PSU): integrated into Mainboard
MainBoard: MSAV3220-ZC26-02 (B)
IC MainBoard: CPU MSD308BT; DRAM: K4B1G1646G; SPI: 25Q64, 25Q32, 25L4005
Tuner: YC
Technical Specifications MTV-2224LT2
MYSTERY MTV-2224LT2
General repair guidelines for TV LCD LED
Repair of electronic devices, including the MYSTERY MTV-2224LT2 TV, it is advisable to start with an external examination of its external and internal elements. In some cases, visible external damage to the elements can suggest the direction of troubleshooting and localization of the defect even before the start of the necessary measurements at the control points of the nodes of electronic circuits. Elements with visible damage, for example, capacitors swelled up after boiling the electrolyte, charred resistors in certain nodes of the circuit, as well as ring cracks in solders will help the master to guess the causes and possible consequences of the malfunction.
Sometimes the MYSTERY MTV-2224LT2 TV simply does not turn on. No control lights on the front panel are lit or blinking, the TV does not respond to the remote control and does not make any sounds or any signs of life when turned on. The most likely cause of the malfunction is a failure of the common power module. If it is working properly, you need to check the processor batteries on the SSB (Main Board). First of all, it is necessary to replace the swollen capacitors of the rectifier filters, if any. If the mains fuse is broken in the power supply, in most cases a breakdown of the power key (s) is detected, which can be integrated with the PWM controller, or a separate field-effect transistor can be used. The rectifier bridge diodes and the electrolytic capacitor of the mains rectifier filter should also be checked.
It should be borne in mind that in the practice of repair it is extremely rare that key transistors in switching power supplies (SMPS) fail for no reason that should be sought by checking other components, for example, a breakdown of the key can provoke faulty elements of the damper circuits, or dried electrolytic capacitors or dangling primary resistors BP circuits involved in the stabilization process. In this case, all semiconductor elements of the strapping of the PWM controller chip are subject to verification, which it is desirable to verify by replacement.
In cases where the MYSTERY MTV-2224LT2 TV has lost its image, and the sound is there and all the other functions are operational, there is a possibility of a malfunction of the LED driver (converter for powering the backlight LEDs of the CLAA215FA10 panel). When you turn on the TV, the image may appear briefly and disappear immediately. It must be borne in mind that with such manifestations the LEDs themselves also fail.
To check the health of the LEDs, as well as contact connections in the ruler circuit, it is necessary to disassemble the panel.
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.
Repair of the motherboard MSAV3220-ZC26-02 (B) must begin with the diagnosis and verification of all linear stabilizers or power converters of its microcircuits. Sometimes it may be necessary to update the software (software) - flashing the FLASH 25Q64B. Firmware included
In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
Remember! Attempts to self-repair by users of the MYSTERY MTV-2224LT2 TV without the appropriate qualifications and the necessary experience can lead to serious negative consequences!

FIRMWARE FOR SPI FLASH  ----------->   MYSTERY MTV-2224LT2 main MSAV3220-ZC26-02(B)
 The appearance of the MainBoard MSAV3220-ZC26-02 (B) is shown in the figure below:
MSAV3220-ZC26-02
MSAV3220-ZC26-02 can be used in TVs:
BBK LEM3284DT2 (Panel LSC320AN02), MYSTERY MTV-2224LT2 (Panel CLAA215FA10), MYSTERY MTV-4028LTA2 (Panel V390HJ1-P02), MYSTERY MTV-4829LTA2 (Panel LSC480HN02-G), MYSTERY MTV-4129LT2 (Panel LK400D3HC34K), MYSTERY MTV-2424LT2 (Panel HM236WU8-200 ), MYSTERY MTV-4030LT2 (Panel V400HJ6-PE1), MYSTERY MTV-4629LTA2 (Panel HV460WU2-200).
Main features of the MYSTERY MTV-2224LT2 device:
Installed matrix (LED-panel) CLAA215FA10.
An integrated LED driver is used to power the backlight LEDs.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit.
MainBoard - the main board (motherboard) is an MSAV3220-ZC26-02 module, using the MSD308BT CPU chips; DRAM: K4B1G1646G; SPI: 25Q64, 25Q32, 25L4005 and others.
The YC tuner provides television reception and channel tuning.
Trademark: MYSTERY, Model: MTV-2224LT2.
Briefly from the TV: LCD, 1080p Full HD, diagonal 22 "(56 cm), HDMI: 2, there is USB, there is support for DVB-T2, backlight type: Edge LED.
The composition uses MainBoard MSAV3220-ZC26-02 (B) and LCD panel (matrix) CLAA215FA10. The power supply is combined with the MainBoard.
MYSTERY MTV-2224LT2 TV with a CLAA215FA10 LCD display, diagonal size 22 "(56 cm) in 16: 9 format. The LED-panel of this TV is equipped with LED backlighting - Edge LED. The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in graphic decomposition according to the standard 1080p (Full HD). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 57 6i, 576p, 720p, 1080i, 1080p Supported media file formats: MP3, MPEG4, DivX, MKV, JPEG.
The power of the sound system 6 W (2x3 W) provide two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, component, VGA, HDMI x2, USB. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 800x600, 1024x768, 1920x1080.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Dimensions: With stand 642x444x209 mm, Without stand 570x345x70 mm.
Attention! The CLAA215FA10 panel of the MYSTERY MTV-2224LT2 LED TV is an expensive and unreliable element.
Avoid any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe to get liquid on the screen. Sometimes one drop is enough if it flows down the glass onto the cables so that the TV becomes unrepairable.