Friday 10 April 2020

REPAIR / SERVICING TV AKIRA LCT-32MT05ST

Technical description and composition of the TV AKIRA LCT-32MT05ST, type of panel and applicable modules. The composition of the modules.
AKIRA
Model: LCT-32MT05ST
Chassis / Version: MSDV2601
Panel: V315B1-L01 Rev. C2
Lamp backlight: 16 Lamp CCFL
T-CON: V315B1-C01; CM2681A-KQ
Inverter (backlight): I315B1-16A
PWM Inverter: OZ964GN
Trans Inverter: 4018L
Power Supply (PSU): MLT666 Rev.2.8 L
PWM Power: MC0628R, L6562D, OB2262
MOSFET Power: 18N50, 6N60C
MainBoard: MSDV2601-ZC01-01 C
IC MainBoard: CPU: MST9E19A; Spi flash: W25X40; AT89C2051; CPU: MST9E19A; SOUND: STA540SA
Tuner: JS-6H2 / 121
Technical Specifications LCT-32MT05ST
AKIRA LCT-32MT05ST
General recommendations for repairing TV LCD
Possible manifestations of defects
- The AKIRA LCT-32MT05ST TV does not turn on and does not show any signs of operability at all. There is no reaction to the remote control and control buttons from the front panel.
With such manifestations, a malfunction is likely to be detected in the MLT666 power supply module. It is necessary to measure the output voltages in its secondary circuits, and if they are completely absent, check the serviceability of the power switches (18N50, 6N60C) and rectifier diodes for possible breakdown (short circuit).
In case of any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And with a short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at 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 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 MC0628R, L6562D, OB2262, in the absence of visible damage or frank fault between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
These manifestations can be triggered by a power module, or by defects in the inverter, as well as a distortion of the currents in the lamps due to their uneven wear. After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, it is necessary to ring in its converter the power switches for breakdown and the secondary windings of the transformers for an open.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the motherboard MSDV2601-ZC01-01 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 some cases, to repair the MB board (SSB), it may be necessary to replace the chips - CPU: MST9E19A; Spi flash: W25X40; AT89C2051; CPU: MST9E19A; SOUND: STA540SA for new or obviously working. In cases where BGA technologies are used, defects are usually localized by the heating method.
Before changing the JS-6H2 / 121 tuner, if it is not possible to tune to television channels, make sure that there are supply voltages that must be measured at the corresponding tuner pins and checked for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Attention TV owners! Attempts to self-repair AKIRA LCT-32MT05ST are not recommended by the manufacturer and can lead to serious negative consequences!


FIRMWARE FOR SPI FLASH  ----------->   AKIRA LCT-32MT05ST, Main: MSDV2601-ZC01-01, Panel: V315B1-L01 Rev.C2

SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    MLT-666

SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    I315B1-16A I315B1-16A Inverter Schematic

 The appearance of the MainBoard MSDV2601-ZC01-01 is shown in the figure below:
MSDV2601-ZC01-01
MSDV2601-ZC01-01 can be used in TVs:
AKIRA LCT-D26MT05ST (Panel V260B1-L02 Rev.C1), AKIRA LCT-32MT04ST (Panel V315B1-L01 Rev.C3), AKIRA LCT-32MT05ST (Panel V315B1-L01 Rev.C2), MYSTERY MTV-2602W (Panel V260B1-L01 Rev.C2 ).
The appearance of the power supply
Key Features of the AKIRA LCT-32MT05ST:
Installed matrix (LCD panel) V315B1-L01 Rev. C2.
The matrix control uses the Timing Controller (T-CON) V315B1-C01 ;.
To power the backlight, an inverter I315B1-16A is used, it is controlled by the PWM controller OZ964GN. A transformer 4018L is installed in the inverter converter.
The necessary supply voltages for all nodes of the TV AKIRA LCT-32MT05ST are generated by the MLT666 power supply module or its analogs using microchips MC0628R, L6562D, OB2262 and power switches of the type 18N50, 6N60C.
MainBoard - the main board (motherboard) is an MSDV2601-ZC01-01 module, using CPU chips: MST9E19A; Spi flash: W25X40; AT89C2051; CPU: MST9E19A; SOUND: STA540SA and others.
The JS-6H2 / 121 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: V315B1-L01
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1366x768, WXGA
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 697.685x392.256 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1500: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 6.5 (G to G)
Frequency: 60Hz
Lamp Type: 16 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V

 Brand: AKIRA, Model: LCT-32MT05ST.
Briefly from the TV: LCD, 32 ", 1366x768, 720p HD, there is PIP, sound: 16 watts.
The composition uses MainBoard MSDV2601-ZC01-01 C and LCD panel (matrix) V315B1-L01 Rev. C2.
Power Supply Unit (PSU) MLT666 Rev.2.8 L Power Supply.
AKIRA LCT-32MT05ST TV with V315B1-L01 LCD, 32 "(81 cm) diagonal size in 16: 9 format. 500 cd / m² screen brightness is provided by CCFL (EEFL) lamps. Contrast - the ratio of maximum brightness to minimum is not less than 1500: 1. It is possible to view in high quality HD at a resolution of 1366x768 pixels in 720p standard (HD Ready). The input high-frequency or video signal is decoded in PAL, SECAM, NTSC analog systems. Digital signal generation (graphic format) is performed in 480i, 480p standards , 576i, 576p, 720p, 1080i.
The power of the speaker system is 16 watts (2x8 watts). 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 x3, S-Video, component, SCART, RGB, VGA, HDMI. A standard VGA (D-Sub 15) connector is used to connect a laptop or computer. This interface supports resolutions: 640x480, 800x600, 1024x768.
Overall dimensions: With stand 731x468x166 mm, Without stand 731x437x87 mm.
Attention! The V315B1-L01 Rev. C2 panel of the AKIRA LCT-32MT05ST LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!