Saturday, 19 December 2020

REPAIRING / SERVICING TV SAMSUNG UE43RU7170U

Technical description and composition of the SAMSUNG UE43RU7170U TV, panel type and modules used.

The composition of the modules.
SAMSUNG LED
Model: UE43RU7170U
Chassis / Version: BN41-02703A
Panel: CY-NN043HGAVCV
LED backlight: BN61-15482A
LED driver (backlight): integrated into PSU
PWM LED driver: BD94062F
MOSFET LED driver: TO-252
Power Supply (PSU): BN44-00947G
PWM Power: PFC, PWM
MOSFET Power: TO-220, TO252
MainBoard: BN41-02703A BN94-14189M
IC MainBoard: CPU, eMMC, DRAM, AUDIO, DC / DC
Tuner: BN40-00331B
Specifications UE43RU7170U
SAMSUNG UE43RU7170U
General recommendations for TV LCD LED repair
Possible manifestations of malfunctions
- TV SAMSUNG UE43RU7170U does not turn on and does not show any signs of operability at all. No response to the remote control and front panel control buttons.
In such cases, the BN44-00947G power supply usually fails. It is necessary to make sure that its output voltages are present and, if they are completely absent, check the power switches (TO-220, TO252) and rectifier diodes for a possible short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in an emergency mode of a short circuit, and with a short circuit in the power elements of the primary circuit, the mains fuse or the current sensor in the source of the key is often cut off.
Breakdown of power switches (MosFet) in switching sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency setting or damper, as well as in the circuits of Negative Feedback (OOS) stabilization. PWM controllers (PWM) PFC, PWM, if they do not have visible damage to the case and an outright short circuit between the pins, are usually checked by replacing.
- There is no picture, but there is sound and reaction to the remote control. Or, for a second, the image may appear immediately after switching on.
Often in such cases, there is no backlighting of the LED panel. The reason may be in the breakage of the backlight LEDs, in the stabilization of their power supply, or in the violation of the contact connections of the BN61-15482A string connectors.
When diagnosing, it must be borne in mind that it is impossible to check for an open in the circuit of the LED lines without disassembling the panels using a tester or multimeter. To open all PN junctions connected in series, a voltage of the order of several tens of volts is required, and ideally a current source. By opening the panel, you can check each LED separately. Typically, Chinese multimeters will lightly light one 3-volt LED if you connect the probes to it in the forward direction. 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 broken through in the SC.
- The TV does not go into operation, does not respond to the remote control. The indicator on the front panel is on or blinking.


Repair or diagnostics of the BN41-02703A 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). Sometimes it is necessary to check or replace (if necessary) the elements of the MainBoard - CPU, eMMC, DRAM, AUDIO, DC / DC. In cases where a BGA processor is used, its malfunction is usually detected by the local warm-up method.
In cases where there is no tuning for terrestrial or cable TV channels, you should make sure that the software is correct, as well as that the supply voltages on the terminals of the BN40-00331B tuner match. It is also necessary to check with an oscilloscope the presence of pulses of data exchange between the tuner and the processor via the I2C bus.
Once again, I remind TV users: you should not try to repair yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repair to professionals with sufficient experience in the field of electronic repair.


Modification of the LED driver after the backlight repair. Information from the master.


Decrease the backlight current from 350 mA 230 mA - increase the resistance of the resistor R9873 (current sensor), in series with the standard 1.0 Ohm, by soldering one pin, you can solder 0.47 Ohm in the BN44-00947G power supply.
Backlight driver current limiting. BD94062F. General recommendations
To reduce the backlight current in LED drivers with the BD94062F controller, you should proportionally increase the resistance of the measuring low-resistance current sensor resistor in the source of the converter IC.

DOWNLOAD SCHEMATIC DIAGRAM     ------------------>    BD94062F

 

 The appearance of the MainBoard BN41-02703A is shown in the figure below:




BN41-02703A
External view of the power supply
Main features of the SAMSUNG UE43RU7170U device:
Installed matrix (LED panel) CY-NN043HGAVCV.
A converter combined with a power supply is used to power the backlight LEDs, and is controlled by a BD94062F PWM controller. TO-252 switches are used as power elements of the LED driver.
The formation of the necessary supply voltages for all nodes of the SAMSUNG UE43RU7170U TV is carried out by the BN44-00947G power module, or its analogs using PFC, PWM microcircuits and power switches of the TO-220, TO252 type.
MainBoard - the main board (motherboard) is a BN41-02703A module, using CPU, eMMC, DRAM, AUDIO, DC / DC and others.
Tuner BN40-00331B provides reception of television programs and tuning to channels.

 


SAMSUNG UE43RU7170U TV with LCD CY-NN043HGAVCV, diagonal size 42.5 "(108 cm) 16: 9 format. The display technology of this model is implemented with LED backlighting.
CY-NN043HGAVCV sensor and MainBoard BN41-02703A software are capable of realizing images in the highest UHD quality at a resolution of 3840x2160 pixels in 4K UHD, HDR standard. Image processing is carried out using modern High Dynamic Range (HDR) technology with an extended range of brightness gradations.
The UE43RU7170U TV is equipped with SMART software, built-in applications and the ability to work on the Internet. The connection to the network can be carried out via Wi-Fi wireless connection. Supported media file formats: MP3, WMA, MPEG4, HEVC (H.265), MKV, JPEG.
Speaker sound system power 20 W (2x10 W) is provided by two speakers. The NICAM stereo audio processing system and the Sound Surround function are used.
Communication with other devices via an external interface is supported by standard input and output connectors: antenna input (RF), AV, component, HDMI x3, USB x2, Ethernet (RJ-45), Bluetooth, Wi-Fi, Miracast. The digital tuner is capable of receiving television channels in the DVB-T, DVB-T2, DVB-C, DVB-S, DVB-S2 standards.
The power consumed when operating from the network is 120 W. Power supply BN44-00947G.
Dimensions: with stand 970x636x210 mm, without stand 970x563x58 mm.
TV weight: with stand: 9.8 kg, without stand: 9.6 kg.


Attention! Panel CY-NN043HGAVCV LED TV SAMSUNG UE43RU7170U 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.


There are files to download for model UE43RU7170U  from the manufacturer:
Latest software updates, firmware (latest firmwares):


File type File name Version Date Size
Update file (USB) T-MSLDEUC.zip 1371.0 10/16/2020 1284.07 Mb
Update instruction 2019_TV_Firmware_Upgrade_Instruction_T-MSLDEUC.pdf 1.0 16.06.2020 0.49 Mb
Update file (USB) T-MSLDEUC_1371.0.exe 1371.0 10.16.2020 1283.78 Mb
Update file (USB) T-MSLDEUC_1371.0_RU.exe 1371.0 10.16.2020 1283.78 Mb


User Manuals and Instructions:


File type File name Version Date Size
User manual BN68-09495D-00_URU7100H_EN_L02_190215.1.pdf 00 13.03.2019 0.86 Mb
Brief instructions BN68-09510A-00_QSG_URU7100H_CIS_190208.0.pdf 00 03/13/2019 0.45 Mb
PDF manual MUSDVBEUR-3.0.5_EM_MUSE_EU_ENG_201026.0.pdf 3.0.0 29.11.2020 22.13 Mb
Instruction PDF MUSDVBEUR-3.0.5_EM_MUSE_EU_RUS_201026.0.pdf 3.0.0 29.11.2020 22.11 Mb


Files can be downloaded from the manufacturer's website -------------------- >>>>  for the UE43RU7170U   model.