Technical description and composition of the SONY KDL-20S2020 TV, panel type and applicable modules. The composition of the modules.SONY
Model: KDL-20S2020
Chassis / Version: SE1
Panel: V201B1-L01
T-CON: 35-D005921 - V201B1-C
Inverter (backlight): PCB2684 - A06-126313 F - CSN306-00
Power Supply (PSU): 1-870-636-11 - 1-727-578-11 - A-1189-417-A G3
PWM Power: MCZ3001DB, STR-A6169
MOSFET Power: 2SK3469
MainBoard: 1-870-688-11, 1-870-681-11
IC MainBoard: VCT6973G, 24C32, TDA9974AHS / 8/12, D61123F1, HY27US08281A
Tuner: BTP-HC401Z
Technical Specifications KDL-20S2020
SONY KDL-20S2020
General recommendations for repairing TV LCD
Diagnostics of the malfunction of the TV SONY KDL-20S2020, like all others, it is advisable to start with an external examination of possible changes, both external and internal elements. In some cases, visible external damage to the elements can suggest directions for troubleshooting and localizing the defect before starting the necessary measurements at the control points of the nodes of electronic circuits. Experienced repairmen are often aware of the causes of the defect and possible consequences, for example, from ring cracks in the soldering of the leads of the elements, as well as from swollen capacitors or resistors burnt to coal dust and other external indirect signs.
Sometimes the SONY KDL-20S2020 TV simply does not turn on. No control lights on the front panel are lit or blinking, the TV does not respond to the remote control and does not make any sounds or any signs of life when turned on. The most likely cause of the malfunction is the failure of the common power module A-1189-417-A 1-870-636-11. It is advisable to start the troubleshooting of the power supply module by checking the mains fuse. If it is broken, it is necessary to check first of all the power semiconductor elements - rectifier diodes and the power switch of the converter, which are often found in breakdown conditions in such situations.
Power switches in flyback converters fail extremely rarely for no reason and, if they are broken, it is necessary to look for a malfunction in the stabilization circuits by checking electrolytic capacitors, semiconductor devices, and resistors in the primary circuit. The cause may be a malfunction of the PWM controller chip, which can only be checked by replacing it with a new or obviously working one.
If the power module uses an active KKM circuit (power factor control), troubleshooting is somewhat more complicated.
In cases where the SONY KDL-20S2020 TV has lost an image, and the sound is there and all the other functions are functional, there is a possibility of a malfunction of the inverter (converter for powering the backlight). When you turn on the TV, the image may appear briefly and immediately disappear. It must be borne in mind that with such manifestations, the lamps themselves also fail, the malfunction of which can be detected by replacement, by connecting to the connectors for diagnostics that are known to be serviceable and suitable in power.
The operation of the power circuits of the inverter and the backlight in the normal mode are controlled by special protection, which is organized for fire safety, for example, to disconnect during short circuits or breaks in high-voltage connections or when the lamps are depressurized. This protection makes it difficult to diagnose and repair the inverter.
All necessary precautions must be observed when disabling the inverter protection during diagnostics and not leaving it disconnected after the repair is completed.
In some cases, to repair the MB (SSB) board, it may be necessary to replace the chips - VCT6973G 24C32 TDA9974AHS / 8/12, D61123F1, HY27US08281A with new or obviously working ones.
Attention to the owners! Attempts at self-repair of the SONY KDL-20S2020 TV are not recommended by the manufacturer and can lead to serious negative consequences!
Service manual / schematic diagram -------------> Sony KDL-20S2000, KDL-20S2020 CHASSIS SE-1
The appearance of MainBoard 1-870-688-11 is shown in the figure below:1-870-688-11
1-870-688-11 can be used in TVs:
SONY KDL-20S2020 (Panel V201B1-L01), SONY KDL-26U2000 (Panel LTA260W2-L19), SONY KDL-32U2000 K (Panel LTA320W2-L14).
The appearance of the power supply
Main features of the device SONY KDL-20S2020:
Installed matrix (LCD panel) V201B1-L01.
The matrix control uses the Timing Controller (T-CON) 35-D005921.
To power the backlight used inverter PCB2684.
The necessary supply voltages for all components of the SONY KDL-20S2020 TV are generated by the power module 1-870-636-11, or its analogs using microchips MCZ3001DB, STR-A6169 and power switches of the type 2SK3469.
MainBoard - the main board (motherboard) is a module 1-870-688-11, using VCT6973G, 24C32, TDA9974AHS / 8/12, D61123F1, HY27US08281A and others.
The BTP-HC401Z tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: V201B1-L01
Type: a-Si TFT-LCD, Panel
Diagonal size: 20.1 inch
Resolution: 1366x768, WXGA
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 444.633x249.984 mm
Surface: Antiglare (Haze 40%), Hard coating (3H), Reflection 2.0% (Max.)
Brightness: 500 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.2M (6-bit + FRC), CIE1931 75%
Response Time: 8 (G to G)
Frequency: 60Hz
Lamp Type: 5 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V
