Monday 6 January 2020

REPAIR / SERVICING TV SAMSUNG UE32F4020AW

Technical description and composition of the SAMSUNG UE32F4020AW TV, panel type and applicable modules. The composition of the modules.
SAMSUNG LED
Model: UE32F4020AW
Chassis / Version: HD06
Panel: CY-HF320AGLV1V // LSF320-AN01-A01
LED backlight: D2GE-320SC0-R0 (13.04.23), 32 SHARP BN41-02017A
LED driver (backlight): integrated into PSU; 146V 240mA
PWM LED driver: BD8174MU
Power Supply (PSU): BN44-00604B
PWM Power: 2S110
MOSFET Power: 12N60NZ
MainBoard: BN41-01955B BN94-06627ะก
IC MainBoard: CPU: SEMS29; DRAM: K4B1G1646G-BCKO; SPI Flash: W25Q40BL; EEPROM: S24C256C;
Tuner: DT0540EIH035A BN40-00256A
Control: IR: A26402B (BN41-01976B)
Technical Specifications UE32F4020
SAMSUNG UE32F4020AW
General repair guidelines for TV LCD LED
Repair of TVs, as well as other devices, it is advisable to start with an external examination. Based on visible external changes in the state of the components, it is often possible to determine the direction of the troubleshooting before making the necessary measurements. Elements with visible damage, for example, capacitors swelled up after boiling the electrolyte, charred resistors in certain nodes of the circuit, as well as ring cracks in solders will help the master to guess the causes and possible consequences of the malfunction.
In cases where the SAMSUNG UE32F4020AW TV does not turn on, does not respond to the remote control and buttons, no indicators on the front panel light up or blink and there are no sounds and no signs of operability at all, the BN44-00604B power supply module is most likely faulty or missing standby power. After checking the mains fuse and power elements of the primary power supply circuit, you should also check for the presence of a short circuit in the loads of the secondary rectifiers.
It should be remembered that in the practice of repair, usually the power switches in switching power supplies (SMPS) do not fail due to their poor quality and, in such cases, it is necessary to look for the cause that led to a malfunction and provoked a breakdown of the key. Most often, the culprits of the accident are dried electrolytic capacitors or dangling resistors in the primary circuit, or the PWM controller chip itself may be faulty. It is also necessary to check all the semiconductor elements of the stabilization circuit in the primary and secondary circuits.
If, when you turn on the TV, the image appears and immediately disappears, or is initially absent when you turn on, but the sound has other functions that work, there is a high probability of a malfunction of the LED driver (power converter for the backlight LEDs CY-HF320AGLV1V LSF320-AN01-A01).
To check the health of the LEDs, as well as contact connections in the ruler circuit, it is necessary to disassemble the panel.
When diagnosing, it is necessary to take into account that it is impossible to check the open in the chain of 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.
If the motherboard BN41-01955 is faulty, first of all it is necessary to check all the linear stabilizers and power converters of its chips, and also, if necessary, update the software (software). Sometimes you can check the health of MB only by replacement.
Often, the MB (SSB) card must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - CPU: SEMS29; DRAM: K4B1G1646G-BCKO; SPI Flash: W25Q40BL; EEPROM: S24C256C; and replace failed chips with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board. Typically, such defects are detected by local heating of the chip.
In the absence of tuning to the local television channels, you should make sure that the software is correct, as well as the presence of supply voltages at the terminals of the tuner DT0540EIH035A BN40-00256A.
Attention to users! Self-repair of a SAMSUNG UE32F4020AW TV without the appropriate qualifications and experience can lead to its complete non-repairability!


SCHEMATIC ------------->  Chassis: U85B, U85C. Models: UE**F5000A*, UE32F4800AW, UE**F5005AK, UE**F5020AK, UE**F5070SS, UE32F40**AW



The appearance of the MainBoard BN41-01955B is shown in the figure below:
BN41-01955B
BN41-01955B can be used in TVs:
Samsung UE32F4000AW (Panel CY-HF320AGLV1V), SAMSUNG UE32F4020AW (Panel CY-HF320AGLV1V), SAMSUNG UE39F5020AK (Panel CY-HF390BGMV1V), SAMSUNG UE39F5000AK UE39F53V (Panel).
The appearance of the power supply
Main features of the SAMSUNG UE32F4020AW device:
Installed matrix (LED panel) CY-HF320AGLV1V or LSF320-AN01-A01.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by the BD8174MU PWM controller.
The formation of the necessary supply voltages for all nodes of the SAMSUNG UE32F4020AW TV is carried out by the BN44-00604B power module or its analogs using 2S110 microcircuits and 12N60NZ power switches.
MainBoard - the main board (motherboard) is a BN41-01955B module, using CPU chips: SEMS29; DRAM: K4B1G1646G-BCKO; SPI Flash: W25Q40BL; EEPROM: S24C256C; and others.
The tuner DT0540EIH035A BN40-00256A provides the reception of television programs and tuning to channels.