Wednesday, 29 April 2020

REPAIR / SERVICING TV MYSTERY MTV-2224LW

Technical description and composition of the MYSTERY MTV-2224LW TV, type of panel and applicable modules. The composition of the modules.
MYSTERY LED
Model: MTV-2224LW
Chassis / Version: V1L12
Panel: M215HG-LE4 Rev. C3
LED driver (backlight): integrated into MainBoard
PWM LED driver: AP3039AM, AP3608E
Power Supply (PSU): integrated into MainBoard
PWM Power: OB2273 (PWM SOT23-6)
MainBoard: MSTV2407-ZC01-01
IC MainBoard: CPU: MST6E182VG-LF, SPI Flash: EN25Q32, Audio: TPA3113D2
Tuner: F35WT-2A-E
Technical Specifications MTV-2224LW
MYSTERY MTV-2224LW
General repair guidelines for TV LCD LED
Repair and diagnostics of any electronic device, in particular MYSTERY MTV-2224LW, it is advisable to start with a careful external examination of internal and external elements. Often, based on certain external signs, it may be possible to draw certain conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. Swollen electrolytic or cermet capacitors, charred resistors, ring cracks in the soldered terminals of the elements - all this can significantly help the master to determine the causes and consequences of the malfunction of the TV.
In cases when the MYSTERY MTV-2224LW TV does not turn on, does not respond to the remote control and buttons, no indicators on the front panel light up or blink, and there are no sounds and no signs of operability when turning on, the power module is most likely faulty or there is no power processor on the motherboard (a typical defect of some MYSTERY TVs). Diagnostics and repair of the common power supply should always begin with a check of the mains fuse and the condition of the electrolytic capacitors of the secondary rectifier filters. Defective and swollen capacitors should be replaced with new ones. If the fuse breaks, it is advisable to check for a breakdown, first of all, all the power semiconductor elements of the converter and the diode bridge of the rectifier network, as well as the large electrolytic capacitor of the filter of the rectifier network.
Mos-Fet keys used in switching power supplies (SMPS) rarely fail for no reason to look for when checking other circuit elements. Often the breakdown is caused by malfunctions of electrolytic capacitors or semiconductor elements in the primary circuit, or by a break in the resistors in the stabilization circuits. The PWM controller chip can also cause a breakdown of the power switch of the converter.
In cases where the MYSTERY MTV-2224LW TV has lost an image, and the sound is there and all the other functions are functional, there is a possibility of a malfunction of the LED driver (converter for powering the backlight LEDs of the M215HG-LE4 Rev.C3 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 and contact connections in their power circuit, the panel must be disassembled.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required.
The motherboard MSTV2407-ZC01-01 must be checked if there is no reaction to the remote control and function buttons, the standby indicator blinks or lights up continuously. In such cases, if the converters or power regulators of the microcircuit are working, a software update may be necessary.
In some cases, it is necessary to check or replace (if necessary) the elements of the MB board (SSB) - Cpu - MST6E182VG-LF, SPI Flash - EN25Q32, Tuner - F35WT-2A-E. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
Before changing the F35WT-2A-E tuner, if it is not possible to tune to television channels, make sure that there are supply voltages, including varicap supply (30-33V), which must be measured on the corresponding tuner pins.
Owners and users of the MYSTERY MTV-2224LW TV must remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!


SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    MSTV2407-ZC01-01


Applicable in TVs: BBK LEM2681F, BBK LEM2682, BBK LEM2284F ... MYSTERY MTV-3018LW, MYSTERY MTV-2211LW V9M01, MYSTERY MTV-2224LW ... Haier: LE32E1600, LE32H320D, LE32B50

To reduce the backlight current in LED drivers with the AP3039AM controller and the AP3608EM terminal stage (AP3039AM-G1 & AP3608EM-G1), the AP3608EM (AP3608E) microcircuit should proportionally increase the resistor from terminal 14 (ISET) to the housing. The maximum current in each channel (in milliamperes) for the Rset resistor (in kilo-ohms) is determined from the ratio 1.194V / Rset. In channels connected in parallel, the currents add up.
Repair MainBoard
The appearance of the MainBoard MSTV2407-ZC01-01 is shown in the figure below:
MSTV2407-ZC01-01
MSTV2407-ZC01-01 motherboard is combined with a power module. The processor is MST6E182VG, or MST6E181VG, made using BGA technology. Repair of the power module is carried out according to conventional technology, starting with checking its power elements. The following is a functional check of the converters for the processor power: + 1.3V, + 1.8V, 3.3V, based on SY8008B PWM controllers. The power supply of the built-in DDR 2.5V is generated from a 3.3V source using the P-N junction of the 1N4001 diode (3.3V-0.8V = 2.5V). Standby mode is organized from the linear stabilizer series 1117-3V3. The LCD panel is powered by either 5V or 12V, depending on the type of panel used.
MSTV2407-ZC01-01 can be used in TVs:
BBK LEM2249HD Ver2 (Panel LM215DT5D), BBK LEM2284F (Panel M215HG-LE4 Rev.C3), BBK LEM2681F (Panel V260H1-LE10 Rev. C1 ), BBK LEM2682 LEM2682DT (Panel V260B2-LE11 Rev.C1), BBK LEM3284F (Panel HV320WXC-200), Haier LE32T1000 (Panel T320XVN09.0), MYSTERY MTV-2224LW (Panel M215HG-LE4 Rev.C3), MYSTERY MTV-3222LW (Panel T320XVN01.0), MYSTERY MTV-1924LW (Panel V185B1-L17), MYSTERY MTV-3018LW (Panel V290BJ1-PE1), MYSTERY MTV-1911LW (Panel HT185WX7-100), MYSTERY MTV-1922LW (Panel V185B1-L17), MYSTERY MTV-1913LW (Panel HT185WX7-100), MYSTERY MTV-3218LW (Panel HV320WX2-20A), MYSTERY MTV-1918LW (Panel V185B1-L17), MYSTERY MTV-2213LW (Panel M215HGE-L10), MYSTERY MTV-2222LW (Panel M215HG-LE4 REV.C3), MYSTERY MTV-2418LW (Panel HM236WUA-100), MYSTERY MTV-2424LW (Panel HM236WU8-100), MYSTERY MTV-1914LW (Panel V185B1-L15 Rev.c1), MYSTERY MTV-3223LW (Panel LK315T3HB94), MYSTERY MTV-2422LW (Panel HM236WU8–100), MYSTERY MTV-3224LW (Panel T320XVN09.0), MYSTERY MTV-2218LW (Panel CLAA215FA10), MYSTERY MTV-1911WL (Panel V185B1-L15 REV.C1), MYSTERY MTV-3221LW (Panel HV320WX2-268), MYSTERY MTV-2211W (Panel M215HG-LE4 ).
Main features of the MYSTERY MTV-2224LW device:
Installed matrix (LED-panel) M215HG-LE4 Rev. C3.
To power the backlight LEDs, a converter is used, combined with the main board MSTV2407-ZC01-01, controlled by the AP3039AM, AP3608E PWM controller.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using OB2273 microcircuits (PWM SOT23-6).
MainBoard - the main board (motherboard) is an MSTV2407-ZC01-01 module, using Cpu microcircuits: MST6E182VG-LF, SPI Flash: EN25Q32, Audio: TPA3113D2 and others.
The F35WT-2A-E tuner provides television reception and channel tuning.


The MYSTERY MTV-2224LW TV with an M215HG-LE4 LCD display, diagonal size 22 "(56 cm), 16: 9 format. The required screen brightness of 250 cd / m² is provided by LED backlighting. Contrast, as the ratio of maximum brightness to minimum, is 1000: 1. The LED-panel of this TV has end-face LED illumination - Edge LED.The TV design and technical features include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in graphic resolution according to the standard 1080p (Full HD). frequency or video signal can be processed in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i. Supported media file formats: MP3, JPEG.
The power of the sound system 6 W (2x3 W) provide two speakers. The audio processing system NICAM STEREO is used.
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. 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: 640x480, 800x600, 1024x768, 1280x1024, 1360x768.
The power consumed by the TV in the operating mode from the network is 38 watts.
Dimensions: With stand 642x444x209 mm, Without stand 570x345x70 mm.
Attention! The M215HG-LE4 Rev. C3 panel of the MYSTERY MTV-2224LW LED TV is an expensive and unreliable element.
Avoid any impact on the glass and pressure on the surface of the screen 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.