REPAIRING / SERVICING TV SAMSUNG UE43RU7200U

Technical description and composition of SAMSUNG UE43RU7200U TV, type of panel and modules used. Module composition.

SAMSUNG LED
Model: UE43RU7200U

Chassis/Version: BN41-02703A

Panel: CY-NN043HGEVJH

LED backlight: BN61-15482A NU7100F NU7000F N5500F V8N1-430SM0-R0

LED driver (backlight): integrated into MainBoard

PWM LED driver: BD94062F

MOSFET LED driver: TO-252

Power Supply (PSU): BN44-00947G L43E7_RDY

PWM Power: PFC, PWM

MOSFET Power: TO-220, TO252

MainBoard: BN41-02703A BN94-14180H

IC MainBoard: CPU, eMMC, DRAM, AUDIO, DC/DC

MainBoard: BN40-00331B

Specifications UE43RU7200U
SAMSUNG UE43RU7200U
General advice for LCD LED TV repair
Possible Manifestations of Faults

- SAMSUNG UE43RU7200U TV does not turn on at all. Control lights do not light up or blink. The TV does not respond to the remote control or control panel buttons.

In these cases, the problem is first to be found in the power supply module BN44-00947G. Then we recommend to measure its output voltages, and in the absence of those, check the serviceability of the power switches (TO-220, TO252) and the inverter rectifier diodes for possible short circuits.
In the event of any breakdown of the semiconductors in the secondary circuits, the inverter can usually operate normally in the faulty short-circuit mode. There are no output voltages present. In the case of short-circuits in the primary circuit, the mains fuse and, less frequently, the current sensor at the source of the switch are usually blown.
The breakdown of power switches (MosFet) in switching supplies is sometimes caused by faults in other circuit elements, e.g. in the circuits supplying the PWM controller, the frequency pick-up or damping circuits, as well as in the negative feedback (negative feedback) stabilisation circuits. PWM regulators (PFC) PFC, PWM, unless they have visible housing damage and outright short circuits between pins, are usually checked by replacement.

- No display, but there is sound and all other functions work. Sometimes the image appears for a second when switching on and then disappears.

In such cases, it is more likely that the LED panel's backlighting elements are faulty. Most often the cause is a breakage of the LEDs, or poor contact in the connectors of the boards, less often the LED-driver may be faulty.
It is better to use a power supply with a maximum voltage of 200V to check if the LEDs are working. It is not recommended to use any voltage source for this purpose. You can check each LED individually with a simple Chinese multimeter (9 volt) in P-N junction mode. If you connect the red probe of the multimeter to the anode of the LED and the black probe to its cathode, the 3 V LED will light up slightly and in the opposite direction you can find the junction of the faulty regulator. The functionality of the PN junction is indirectly a proof of the functionality of the LED.

- The TV set doesn't switch on, the remote control isn't responding. LED is blinking or in standby mode.

Repair or diagnostic of the BN41-02703A motherboard should begin with a check of the stabilisers and power converters necessary to power the microcircuits and the matrix. If necessary, software (firmware) should be updated or replaced. In some cases repair of MB board (SSB) may require replacement of chips - CPU, eMMC, DRAM, AUDIO, DC/DC with new or known good ones. In cases where BGA technology is used, defects can usually be repaired by heating.

Before replacing your BN40-00331B tuner if there is no tuning to the channels, you should first check the software and the supply voltage on its outputs. You should also check whether the tuner and the processor can communicate via I2C bus.

Warning. I strongly recommend for the users and owners of UE43RU7200U, which have no appropriate skill, knowledge and experience, not to try to make repairs themselves in order to avoid the negative consequences, which can lead to the complete uselessness of the device.

Backlight driver current limitation. BD94062F. General recommendations

To reduce backlight current in LED drivers with the  controller the resistance of the current sensor measuring low resistor at the source of the converter switch should be increased proportionally.

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


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

BN41-02703A

Appearance of MainBoard

The main features of the SAMSUNG UE43RU7200U:

A matrix (LED panel) CY-NN043HGEVJH is installed.
A converter combined with a BN41-02703A main board, controlled by a BD94062F PWM controller, is used to power the backlight LEDs. TO-252-type switches are used as power elements of the LED driver.
The power supply module BN44-00947G or its analogues with the use of PFC, PWM chips and TO-220, TO252 power switches form the necessary supply voltages for all the nodes of SAMSUNG UE43RU7200U TV.
MainBoard - the main board (motherboard) is BN41-02703A module, using CPU, eMMC, DRAM, AUDIO, DC/DC and other microchips.
The BN40-00331B tuner is used to receive TV programmes and tune to channels.

Instructions and updates

The Samsung website has a firmware (software update) for UE43RU7200UXRU, version 1371.0 from 10/16/2020. 

 

There are files to download for the SAMSUNG UE43RU7200U  model 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

User Manuals and Instructions:
File type File name Version Date Size
User manual BN68-09495N-00_URU7100H_EN_L02_190517.0.pdf 00 06/18/2019 0.9 Mb
Instruction PDF MUSDVBEUR-3.0.5_EM_MUSE_EU_ENG_201026.0.pdf 3.0.0 29.11.2020 22.13 Mb

Files can be downloaded from the manufacturer's website for the SAMSUNG UE43RU7200U   model.


SAMSUNG UE43RU7200U TV with LCD CY-NN043HGEVJH, diagonal size 43 "(109 cm) 16: 9 format. The display technology of this model is implemented with LED backlighting.
The CY-NN043HGEVJH sensor and the MainBoard BN41-02703A software are capable of realizing images in the highest UHD quality at 3840x2160 pixels in 4K UHD, HDR. Image processing is performed using modern High Dynamic Range (HDR) technology with an extended range of brightness gradations.
The UE43RU7200U 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 970x648x344 mm, without stand 970x563x58 mm.

TV weight: with stand: 12.1 kg, without stand: 9.5 kg.

Attention! Panel CY-NN043HGEVJH LED TV SAMSUNG UE43RU7200U 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.