Tuesday 17 March 2020

REPAIR / SERVICING TV TCL LED32D2900

Technical description and composition of the TCL LED32D2900 TV, panel type and applicable modules. The composition of the modules.
TCL LED
Model: LED32D2900 LED32D2900S
Chassis / Version: TP.S512.PB775
Panel: ST3151A05-8 Ver. 2.4
LED backlight: 32HR330M06A5 4C-LB3206-HR03J
T-CON: MT3151A05-5-XC-9; CSH11-C0H, CS902-A, CS801-B
LED driver (backlight): integrated into MainBoard
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.S512.PB775 SI512SP1 (V8-S512BP-LF1V068)
IC MainBoard: 25Q64CSIG, GB98AERN, TPA3110LD2, RT5047B,
Tuner: R840 (Rafael Micro)
Technical Specifications LED32D2900
TCL LED32D2900
General repair guidelines for TV LCD LED
Possible malfunctions
- TCL LED32D2900 TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
In such cases, the AC / DC converter of the mains voltage, which is combined with the main board TP.S512.PB775, is often faulty. It is necessary to measure its output voltages and, if they are absent, to check the short circuit probability in the converters power switches and rectifier diodes.
In case of breakdowns of semiconductors in the secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM SOT23-6 PWM chips are usually checked by replacing with new ones, or obviously working.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
In most of these cases, a malfunction is detected in the nodes and backlight elements of the LED panel. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
To check the health in the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED individually with a simple Chinese multimeter (powered by 9 volts) in the P-N-junction test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. A zener diode PN junction indirectly indicates a LED-a
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the TP.S512.PB775 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Checking or replacing elements 25Q64CSIG, GB98AERN, TPA3110LD2, RT5047B, requires the necessary training and professional skills in repairing modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by warming up.
Once again, remind users! Attempts to self-repair a TV TCL LED32D2900 without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!


FIRMWARE FOR SPI FLASH ------------>  TCL LED32D2900 LED32D2900S, Main: TP.S512.PB775, Panel: LWD320CS0T E284 V2 T8-32D2900

 
 The appearance of MainBoard TP.S512.PB775 is shown in the figure below:
TP.S512.PB775
TP.S512.PB775 can be used in TVs:
TCL LED40D2900 (Panel LVF400SSOT), TCL LED32D2900 LED32D2900S (Panel ST3151A05-8 Ver.2.4).
Main features of the TCL LED32D2900 device:
Installed matrix (LED panel) ST3151A05-8 Ver.2.4.
The matrix control uses the Timing Controller (T-CON) MT3151A05-5-XC-9 ;.
To power the backlight LEDs, a converter is used, combined with the main board TP.S512.PB775.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PWM SOT23-6 microcircuits.
MainBoard - the main board (motherboard) is a TP.S512.PB775 module, using 25Q64CSIG, GB98AERN, TPA3110LD2, RT5047B chips, and others.
The R840 tuner (Rafael Micro) provides TV reception and channel tuning.

 TCL LED32D2900 TV with an ST3151A05-8 LCD display, 32 "(81 cm) diagonal size in 16: 9 format. The LED screen technology is implemented in the manufacturing technology of the screen of this TV model. You can view images in high quality HD with a resolution of 1366x768 pixels in the standard 720p (HD Ready) graphic decomposition Supported media file formats: MP3, MPEG4, MKV, JPEG.
The power of the sound system 10 W (2x5 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 x2. An output for connecting headphones is provided.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: with stand 734x482x184 mm, without stand 734x435x81 mm.
TV Weight: with stand: 4.5 kg, without stand: 4.4 kg.
Attention! The ST3151A05-8 Ver.2.4 panel of the TCL LED32D2900 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.