Technical description and composition of the TCL L65P2US TV, panel type and applicable modules. The composition of the modules.TCL LED
Model: L65P2US
Chassis / Version: MS68A
Panel: 3840x2160 4K UHD
LED driver (backlight): integrated into PSU
PWM LED driver: OZ9976AGN
Power Supply (PSU): 40-L301H4-PWB1CG 08-L301WA4-PW200AB
MainBoard: 40-MS68AD-MAC2HG
IC MainBoard: CPU: MS6488, EMMC: 16GB, NAND: 4Gb, AUDIO: TAS5707
Tuner: MXL661 & ATBM7812B
Technical Specifications L65P2US
TCL L65P2US
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The TCL L65P2US TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light or flash.
With such manifestations, a malfunction is most likely to be detected in the 40-L301H4-PWB1CG power supply module. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches and rectifier diodes in the converters for a short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more 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 microcircuits are usually checked by replacement with new ones, or obviously working.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
The faulty usually in these cases is the backlight matrix (LED-panel). The reason can be found in the malfunction of the LEDs, in the violation of the contact connections of the LED strips, or in the provision of their power (LED driver).
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as a health indicator. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the 40-MS68AD-MAC2HG 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). Sometimes it is necessary to check or replace (if necessary) the elements of the MainBoard - AUDIO: TAS5707 board. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
The malfunction of the tuner MXL661 & ATBM7812B is established after checking the software and all the supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be controlled by an oscilloscope.
TV users and owners need to remember that attempts to self-repair a TCL L65P2US TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!
Service manual / schematic diagram ------------------> Chassis MS68AD MainBoard 40-MS68AD-MAC2HG.rar
The appearance of the MainBoard 40-MS68AD-MAC2HG is shown in the figure below:40-MS68AD-MAC2HG
Main features of the TCL L65P2US device:
Installed matrix (LED-panel) 3840x2160 4K UHD.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by the OZ9976AGN PWM controller.
The formation of the required supply voltage for all nodes of the TCL L65P2US TV is carried out by the 40-L301H4-PWB1CG power supply module, or its analogs.
MainBoard - the main board (motherboard) is a 40-MS68AD-MAC2HG module, using CPU chips: MS6488, EMMC: 16GB, NAND: 4Gb, AUDIO: TAS5707 and others.
The MXL661 & ATBM7812B tuner provides TV reception and channel tuning.
TCL L65P2US TV with a 3840x2160 LCD, diagonal size 65 "(165 cm) in 16: 9 format. LED TV backlighting is implemented in the technology for producing this TV model. You can watch movies in the highest possible quality UHD at a resolution of 3840x2160 pixels in 4K standard UHD.
The L65P2US is equipped with SMART software, embedded applications and the ability to work on the Internet. Connecting to the Internet can be done via Wi-Fi. Supported media file formats: MP3, MPEG4, MKV, JPEG.
The power of the sound speaker system 16 W (2x8 W) is provided by 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, component, VGA, HDMI x3, USB, Ethernet (RJ-45), Wi-Fi. 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 1464x911x247 mm, without stand 1464x843x65 mm.
TV Weight: with stand: 20.6 kg, without stand: 20.3 kg.
Attention! The panel of the 3840x2160 4K UHD LED TV TCL L65P2US 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.
