Monday 9 March 2020

REPAIR / SERVICING TV SONY KDL-43W808C

Technical description and composition of the SONY KDL-43W808C TV, panel type and applicable modules. The composition of the modules.
SONY LED
Model: KDL-43W808C
Chassis / Version: GN1G XM-A
Panel: V430FWME03
LED driver (backlight): 15STM6S-ABC02 REV: 1
PWM LED driver: BD9397EFV
Power Supply (PSU): Adapter 19.5V
MainBoard: 1-980-805-31 (173611531)
IC MainBoard: CPU: Cortex-A12 NEON, EMMC: H26M52103FMR
Tuner: CE241ZP
Technical Specifications KDL-43W808C
SONY KDL-43W808C
General repair guidelines for TV LCD LED
Possible malfunctions
- The SONY KDL-43W808C TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light or flash.
With such manifestations, a malfunction is likely to be detected in the Adapter power module.
This TV model is equipped with an external adapter 19.5V type power supply, which the owner can purchase independently, and repairing it may not always be advisable, however, sometimes there is a certain sense to open it and eliminate simple typical defects typical of IIPS. It is necessary to measure its output supply voltage, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for the probability of breakdown in semiconductor PN junctions.
In case of breakdowns of semiconductors in secondary circuits, the converter can usually operate abnormally in short circuit mode, and during short circuit in the power elements of the primary circuit, the main fuse often breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM), in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
The faulty usually in these cases is the backlight matrix (LED-panel). Often the cause of the malfunction is the lack of current in the LED circuit, for example, an open or short circuit, or a violation of the contact connections of the connectors.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the motherboard 1-980-805-31 should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its CPU chips: Cortex-A12 NEON, EMMC: H26M52103FMR and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
If you suspect a malfunction of the CE241ZP tuner, first of all, you need to verify the correctness of the software, as well as the presence of the necessary voltage levels and pulses of data exchange with the processor via the I2C bus at the corresponding terminals of the tuner.
TV users and owners need to remember that attempts to self-repair a SONY KDL-43W808C TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!


Service manual / schematic diagram  --------------------->  SONY KDL-43W808C Chassis GN1G XM-A

 The appearance of MainBoard 1-980-805-31 is shown in the figure below:
1-980-805-31
Main features of the device SONY KDL-43W808C:
Installed matrix (LED panel) V430FWME03.
The LED driver 15STM6S-ABC02 is used to power the backlight LEDs, it is controlled by the BD9397EFV PWM controller.
To power all the internal components of the SONY KDL-43W808C TV, an external adapter type 19.5V is used.
MainBoard - the main board (motherboard) is a module 1-980-805-31, using CPU chips: Cortex-A12 NEON, EMMC: H26M52103FMR and others.
The CE241ZP tuner provides TV reception and channel tuning.