Monday 30 December 2019

REPAIR / SERVICING TV SAMSUNG UE19H4000

Technical description and composition of the SAMSUNG UE19H4000 TV, panel type and applicable modules. The composition of the modules.
SAMSUNG LED
Model: UE19H4000
Panel: HT185WX1-300
LED backlight: EDGE LED
T-CON: HM185WX1-400.X0.0 47-600375
LED driver (backlight): integrated into PSU
PWM LED driver: BD93941FP
Power Supply (PSU): BN44-00692A
PWM Power: SSC1S311
MainBoard: BN41-02105A BN94-07207P
IC MainBoard: CPU: NT14L, Spi Flash W25Q40BL, Eeprom AT24C256, Audio: NTP7414
Tuner: BN40-00287A
Control: IR: BN41-01976B
Technical Specifications UE19H4000
SAMSUNG UE19H4000
General repair guidelines for TV LCD LED
Possible manifestations of defects
- SAMSUNG UE19H4000 TV does not turn on at all. The control lights do not light or flash. The TV on the remote control and the control panel buttons do not respond.
With such manifestations, the BN44-00692A power module usually fails. Then it is necessary to measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches and rectifier diodes of the converters for the presence of a possible short circuit.
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 power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback (OOS) stabilization circuits. PWM controllers (PWM) SSC1S311, if they do not have visible damage to the case and open short circuit between the terminals, are usually checked by replacement.
- There is no image, there is sound, there is a reaction to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
In such cases, the most likely malfunction of the backlight elements of the LED panel. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
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 test 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 enter the operating mode, does not respond to the remote control. The indicator on the front panel lights up constantly or blinks.
Repair or diagnostics of the BN41-02105A motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, you should update or replace the software (software). When repairing an MB board, you need to check its CPU components: NT14L, Spi Flash W25Q40BL, Eeprom AT24C256, Audio: NTP7414. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
If a tuner BN40-00287A is suspected of malfunction, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary supply voltage levels and data exchange pulses with the processor via the I2C bus at the corresponding tuner pins.
We recommend the owners of the UE19H4000 TV for repair only to qualified specialists with the necessary work experience! Attempts to repair it yourself without the appropriate knowledge and skills can lead to irreversible negative consequences!


The appearance of the MainBoard BN41-02105A is shown in the figure below:
BN41-02105A
BN41-02105A can be used in TVs:
SAMSUNG T24D310EX (Panel V236BJ1-LE2 REV.C5), SAMSUNG UE28H4000AK (Panel HH028AAGH-R1), SAMSUNG T28D310EX (Panel HH028AGH-R2), SAMSUNG UE22H5000 UE22H5000AK (Panel MG28HT28) UE28J4100AK UE28J4100A (Panel HH028AGH-R2 ST2751A02-1).
The appearance of the power supply
Main features of the SAMSUNG UE19H4000 device:
Installed matrix (LED-panel) HT185WX1-300.
The matrix control uses the Timing Controller (T-CON) HM185WX1-400.X0.0.
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by a BD93941FP PWM controller.
The necessary supply voltages for all nodes of the SAMSUNG UE19H4000 TV are generated by the BN44-00692A power module, or its analogs using SSC1S311 microcircuits.
MainBoard - the main board (motherboard) is a BN41-02105A module, using CPU chips: NT14L, Spi Flash W25Q40BL, Eeprom AT24C256, Audio: NTP7414 and others.
The tuner BN40-00287A provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: BOE
Model: HT185WX1-300
Type: a-Si TFT-LCD, Panel
Diagonal size: 18.5 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 409.8x230.4 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 72%
Response Time: 1.5 / 3.5 (Tr / Td)
Frequency: 60Hz
Lamp Type: 10S4P WLED Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V