Technical description and composition of the TV SONY KDL-42W654A, type of panel and applicable modules. The composition of the modules.SONY LED
Model: KDL-42W654A
Chassis / Version: BLE
Panel: T420HVF04.3
LED backlight: 74.42T31.002-0-DX1
LED driver (backlight): ST420AU-4S01 Rev1.0
Power Supply (PSU): ACDP-120N02 Adapter 19.5V 6.2A
PWM Power: PWM
MainBoard: 1-888-390-12 - 173427812 - A1949534B - BLE // A1951270A TU
IC MainBoard: CPU: CXD4748GB, CXD4743GB; DRAM: H5TC4G63MFR; NAND Flash: TC58NVG3S0FTAI0
Tuner: 173427812 A 1951270A A1949520B
Control: RM-ED053, RM-ED052
Appearance
SONY KDL-42W654A
General repair guidelines for TV LCD LED
SONY KDL-42W654A, like other televisions, it is advisable to start repairing with a careful examination of the external and internal elements and modules. Often, based on certain external signs, it may be possible to draw certain conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. Experienced repairmen are often aware of the causes of the defect and the 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.
If the power supply adapter ACDP-120N02 19v5 6v2 fails, the external manifestations may be different, for example, the SONY KDL-42W654A does not turn on at all and there is no indication of the indicator lights on the front panel. With the same symptoms, the stabilizer (converter) of the power supply to the control processor may be faulty. In the absence of swollen filter capacitors of the secondary rectifiers, the diagnostics of the power supply should be started by checking the fuse and, if it is broken, it is first necessary to check all the power semiconductor elements of the primary circuit - diodes and transistors for the possibility of an avalanche or thermal breakdown.
In most cases, key breakdowns in switching power supplies (SMPS) do not occur for no reason and you should look for other faulty circuit elements that could provoke a defect. This can be dried electrolytic capacitors in the primary circuit, and faulty damper elements, as well as dangling resistors or punched semiconductor elements in the stabilization circuits. Possible defective PWM chip from the manufacturer.
If the SONY KDL-42W654A does not have an image, but there is sound and the TV is controlled by the remote control, a malfunction in the backlight circuits of the T420HVF04.3 panel is likely. The LEDs or the power converter - LED driver may be faulty. Often in such cases, when you turn on the TV, an image appears and immediately disappears. First of all, it is necessary to verify the operability of the electrolytic capacitors of the rectifier filter supplying the LED driver, and check the LEDs, connecting obviously known good diagnostics.
In most cases of lack of backlight, it becomes necessary to disassemble the panel in order to check the LEDs, connectors, loops and all contact connections. If one or several LEDs does not work in one line, therefore, they are broken and should be replaced.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally, a current source.
If the motherboard BLE, BLT A1951270A TU is faulty, first of all it is necessary to check all the linear stabilizers or power converters of its chips, and also, if necessary, update the software. Sometimes you can check the health of MB only by replacement.
Remember! Attempts to self-repair by users of the SONY KDL-42W654A TV without the appropriate qualifications and the necessary experience can lead to serious negative consequences!
Service manual / Schematic Diagram ------------------> Sony KDL-32W600A/603A/W605A/607A/650A/651A/653A/654A/655A/656A/658A/670A/674A, KDL-42W650A/651A/653A/654A/655A/656A/657A/658A/670A/674A. CHASSIS RB1G
The appearance of MainBoard 1-888-390-12 is shown in the figure below:1-888-390-12
1-888-390-12 can be used in TVs:
SONY KDL-42W654A (Panel T420HVF04.3), SONY KDL-24W605A (Panel SYV2421-01), SONY KDL-32W603A (Panel T320XVF05.0), SONY KDL-32W653A (Panel T320HVF01.0).
The appearance of the power supply
Main features of the device SONY KDL-42W654A:
Installed matrix (LED panel) T420HVF04.3.
The LED driver ST420AU-4S01 is used to power the backlight LEDs.
To power all the internal components of the SONY KDL-42W654A TV, an external source of the ACDP-120N02 Adapter 19.5V 6.2A type is used using PWM chips.
MainBoard - the main board (motherboard) is a 1-888-390-12 module, using CPU chips: CXD4748GB, CXD4743GB; DRAM: H5TC4G63MFR; NAND Flash: TC58NVG3S0FTAI0 and others.
The tuner 173427812 A 1951270A A1949520B provides the reception of television programs and tuning to channels.