Technical description and composition of the THOMSON T55E88DHU TV, panel type and modules used. The composition of the modules.THOMSON LED
Model: T55E88DHU
Chassis / Version: 3F11
Panel: LTA550HF03
LED backlight: EDGE LED
Power Supply (PSU): KPS-L180C3 - 02
PWM Power: FAN7530, FSGM300, FSFR1700
MOSFET Power: 2SK4108
MainBoard: KDL55JS88AZZ-F3S
IC MainBoard: MSD209GX, W25X40
Specifications T55E88DHU
THOMSON T55E88DHU
General recommendations for TV LCD LED repair
Possible manifestations of defects
- THOMSON T55E88DHU does not turn on and does not show any signs of operability at all. Does not blink indicators and does not respond to control buttons.
With such manifestations, the power supply module KPS-L180C3 usually fails. Its output voltages should be measured and, in their absence, the power switches (2SK4108) and rectifier diodes should be checked for the probability of a short circuit in the converters.
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 FAN7530, FSGM300, FSFR1700, 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 in good working order.
- There is no image, there is sound, it reacts to the remote control, the channels are switched. In some cases, the image appears when turned on and disappears immediately.
Often in such cases, there is no backlighting of the LED panel. The reason for this may be an open circuit in the LED circuit, or a problem in stabilizing their power supply.
It is impossible to detect an open circuit in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and a voltage of several tens of volts is required to open their junctions. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Usually, Chinese multimeters lightly light one 3-volt LED if you connect the probes to it in the forward direction (red probe to the anode, black to the cathode). For dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of LED health. In the event of a malfunction of the LED, its zener diode will either be cut off or pierced in the K / Z.
- The indicator on the front panel blinks, the TV does not turn on in operating mode, does not respond to the remote control.
If THOMSON T55E88DHU has no picture, but there is sound, often the LTA550HF03 display backlight 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 LTA550HF03 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 the 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 KDL55JS88AZZ-F3S often turns out to be faulty, a software failure is also possible.
Then, first of all, it is necessary to check the panel supply voltage, 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 use an oscilloscope to trace the passage of LVDS signals from the MainBoard KDL55JS88AZZ-F3S, 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 ..............
Repair or diagnostics of the KDL55JS88AZZ-F3S motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and matrix. If necessary, you should update or replace the software (software). In cases of complex MB (SSB) repairs and with the necessary skills and equipment, it may sometimes be necessary to replace its MSD209GX, W25X40 chips and other possible faulty components. Malfunctions associated with the use of BGA soldering technologies are usually easily diagnosed by the warm-up method.
We remind users again! Attempts to self-repair a THOMSON T55E88DHU TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> THOMSON T55E88DHU , Main: KDL55JS88AZZ-F3S, Panel: LTA550HF03
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> KPS-L180C3 Power supply
The main features of the THOMSON T55E88DHU device:Installed matrix (LED panel) LTA550HF03.
The formation of the necessary supply voltages for all nodes of the THOMSON T55E88DHU TV is carried out by the KPS-L180C3 power module, or its analogs using FAN7530, FSGM300, FSFR1700 microcircuits and 2SK4108 power switches.
MainBoard - the main board (motherboard) is a KDL55JS88AZZ-F3S module, using MSD209GX, W25X40 and others.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA550HF03
Type: a-Si TFT-LCD, Panel
Diagonal size: 55 inch
Resolution: 1920x1080, FHD
Display Mode: S-PVA, Normally Black, Transmissive
Active Area: 1209.6x680.4 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 450 cd / m²
Contrast Ratio: 5000: 1
Display Colors: 1.06B (8-bit + FRC), CIE1931 80%
Response Time: 6 (G to G)
Frequency: 120Hz
Voltage: 12.0V
Lamp Type: WLED Embedded (LIPS)
Signal Interface: LVDS (4 ch, 10-bit), 92 pins LED backlighting The ratio of maximum to minimum brightness (contrast) is not less than 5000: 1. The LCD panel uses Edge LED backlighting.The design and technical capabilities of the TV provide viewing in high quality HD at a resolution of 1920x1080 pixels in graphic resolution 1080p (Full HD). Input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Digital signal formation (graphic format) is performed in standards 480i, 480p, 576i, 576p, 720p, 1080i. Supported multimedia formats: MP3, MPEG4, MKV, JPEG.
Speaker power of 10 W (2x5 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV x3, audio x4, component, SCART, RGB, VGA, HDMI x4, USB x2. A headphone jack is provided. A standard VGA (D-Sub 15) connector is used to connect a laptop or computer. This interface supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080.
Attention! The LTA550HF03 panel of the THOMSON T55E88DHU LED TV is an expensive and unreliable element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also 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.
