Tuesday 10 March 2020

REPAIR / SERVICING TV SONY KDL-50W828B

Technical description and composition of the TV SONY KDL-50W828B, type of panel and applicable modules. The composition of the modules.
SONY LED
Model: KDL-50W828B
Chassis / Version: RB2G
Panel: T500HVF04.0
LED driver (backlight): 14STM4250AD-6S01 REV: 1.0.
PWM LED driver: BD9422EF
MOSFET LED driver: SBR10150CT
Power Supply (PSU): Adapter 19.5V
MainBoard: 1-889-202-23, 1-889-203-12 (173457512)
IC MainBoard: CXD4748GB, CXD4743GB
Control: IR: 1-889245-11 (173459911), wifi: J20H076
Technical Specifications KDL-50W828B
SONY KDL-50W828B
General repair guidelines for TV LCD LED
Possible malfunctions
- SONY KDL-50W828B does not turn on and does not show any signs of performance at all. Does not blink indicators and does not respond to control buttons.
Most likely in this case, the main switching power supply (IPS) Adapter is faulty.
The owner of the TV can purchase an external power adapter adapter 19.5V type independently and its repair is not always advisable. In any case, the simplest typical defects characteristic of most IIP schemes can be easily detected and eliminated after opening. In the absence of the necessary supply voltages in the secondary circuits of the converters, it is necessary to check the power switches and rectifier diodes for a possible partial or complete breakdown.
In case of breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually breaks.
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 circuits (OOS) of stabilization. PWM controllers (PWM), 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, but there is sound, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
Usually in such cases there is no backlight LED-panel (matrix). The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
When trying to detect a break in the LED lines, it should be taken into account that it is difficult to do this without disassembling the panel. For example, a current source is needed to open PN junctions connected in series.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the 1-889-202-23 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). Board repair and replacement of CXD4748GB, CXD4743GB microcircuits are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
TV users and owners need to remember that attempts to self-repair a SONY KDL-50W828B TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!


Service manual / schematic diagram ------------>   SONY KDL-50W828B Chassis RB2G ; KDL-32W700B, KDL-42W700B, KDL-42W800B, KDL-50W700B, KDL-55W790B, KDL-32W705B, KDL-42W705B, KDL-42W805B, KDL-50W790B, KDL-55W800B, KDL-32W706B, KDL-42W706B, KDL-42W807B, KDL-50W800B, KDL-55W805B, KDL-32W707B, KDL-42W707B, KDL-42W815B, KDL-50W805B, KDL-55W808B, KDL-42W817B, KDL-50W807B, KDL-55W815B, KDL-42W828B, KDL-50W808B, KDL-55W817B, KDL-42W829B, KDL-50W815B, KDL-55W828B, KDL-50W817B, KDL-55W829B, KDL-50W828B, KDL-55W855B, KDL-50W829B, KDL-55W857B



 Main features of the device SONY KDL-50W828B:
Installed matrix (LED-panel) T500HVF04.0.
The LED driver 14STM4250AD-6S01 is used to power the backlight LEDs, it is controlled by the BD9422EF PWM controller. As power elements of the LED driver, keys of the SBR10150CT type are used.
To power all the internal components of the SONY KDL-50W828B TV, an external adapter type 19.5V is used.
MainBoard - the main board (motherboard) is a module 1-889-202-23, using microcircuits CXD4748GB, CXD4743GB and others.

 SONY KDL-50W828B TV with T500HVF04.0 LCD, 50 "(127 cm) diagonal size in 16: 9 format. This model uses side illumination from Edge LEDs.
There is support for 3D images with active (shutter) technology for separating the right and left channels.
The T500HVF04.0 panel and the motherboard software 1-889-203-12 provide for viewing HD and Full HD images at a resolution of 1920x1080 pixels in a graphic decomposition according to the 1080p standard (Full HD).
The KDL-50W828B is equipped with SMART software, embedded applications and the ability to work on the Internet. Connecting to the Internet can be done via Wi-Fi. The input analog video signal can be processed in PAL, SECAM, NTSC systems. Graphic processing and image formation of a digital signal occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Video processor supported media file formats: MP3, WMA, MPEG4, Xvid, MKV, JPEG.

The power of the sound speaker system 16 W (2x8 W) is provided by two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, component, SCART, RGB, HDMI x4, MHL, USB x2, Ethernet (RJ-45), Wi-Fi 802.11n, Miracast. An output for connecting headphones is provided. To connect an analog computer or laptop to this TV model, a VGA (D-Sub 15) connector is used, which supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080.
The digital tuner is capable of receiving television channels in the standards DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2.
Overall dimensions: with stand 1116x693x179 mm, without stand 1116x656x64 mm.
TV Weight: with stand: 14.8 kg, without stand: 13.6 kg.
Attention! The T500HVF04.0 panel of the SONY KDL-50W828B LED TV is its most expensive element.
Avoid hitting the glass and excessive pressure on the screen surface to avoid damage to the LED panel!
It is unsafe to get any liquid on the screen. Sometimes one drop of water is enough, if it flows down the glass onto the cables, the TV can become unrepairable.