Monday 9 March 2020

REPAIR / SERVICING TV SONY KDL-46EX521

Technical description and composition of the TV SONY KDL-46EX521, type of panel and applicable modules. The composition of the modules.
SONY
Model: KDL-46EX521
Panel: LTY460HN02
Lamp backlight: LJ64-02858A S1G1-460SM0-R0 [10.09.08]
T-CON: ESL_C2LV0.4
Inverter (backlight): integrated into PSU
Power Supply (PSU): APS-285 1-883-804-21
MainBoard: 1-883-753-32 603n4049-01R Y2009590F
IC MainBoard: CXD4727GB, K4B2G1646C-HCH9, KFM2GN6Q2B, Y164B, NJU72040, Sil9287BCNU, GL850G
Tuner: CXD2825GA
Technical Specifications KDL-46EX521
SONY KDL-46EX521
General recommendations for repairing TV LCD
Possible malfunctions
- The SONY KDL-46EX521 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.
Most often, with such manifestations, the main power module APS-285 is found to be faulty. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches and rectifier diodes in the converters for a short circuit.
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.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM microcircuits are usually checked by replacement with new ones, or obviously working.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or inverter. If all the electrolytic capacitors of the filter according to the power supply of the inverter are working, make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
Sometimes, for diagnostic purposes, it is necessary to disable the inverter protection. In such cases, special care must be taken during work, and the protection circuits should be restored immediately after the repair is completed.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the 1-883-753-32 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 CXD4727GB, K4B2G1646C-HCH9, KFM2GN6Q2B, Y164B, NJU72040, Sil9287BCNU, GL850G 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.
Before changing the CXD2825GA tuner, if it is not possible to tune to television channels, make sure that there are supply voltages that must be measured at the corresponding tuner pins and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope !
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.

1. Service Manual 86 pages of 2011 FOR  the models KDL-22EX320, KDL-22EX325, KDL-24EX320, KDL-24EX325, KDL-26EX320, KDL-26EX321, KDL-26EX325, KDL-32EX421, KDL-32EX425, KDL-32EX23 , KDL-32EX524, KDL-32EX525, KDL-37EX521, KDL-37EX524, KDL-37EX525, KDL-40EX520, KDL-40EX521, KDL-40EX523, KDL-40EX524, KDL-40EX525, KDL-46EX, KDL-46EX-46EX, 46DL-46EX-46EX -46EX524, KDL-46EX525

 
 2. Service Manual 43 pages of 2011 FOR  the models KDL-32EX421, KDL-32EX423, KDL-32EX520, KDL-32EX520, KDL-32EX521, KDL-32EX521, KDL-32EX523, KDL-32EX523, KDL-40EX520, KDL-40EX520 , KDL-40EX521, KDL-40EX521, KDL-40EX523, KDL-40EX523, KDL-46EX520, KDL-46EX520, KDL-46EX521, KDL-46EX521, KDL-46EX523, KDL-46EX523





The appearance of MainBoard 1-883-753-32 is shown in the figure below:
1-883-753-32
1-883-753-32 can be used in TVs:
SONY KDL-32CX520 (Panel V315H3-L01), SONY KDL-32EX421 (Panel LTY320AN02), SONY KDL-32EX720 (Panel LTY320HJ01), SONY KDL-40EX521 (Panel LTY400HM08 001), SONY KDL-46EX720 (Panel LTY460HJ05 3D), SONY KDL-46CX520 (Panel LTY460HN01), SONY KDL-40CX521 (Panel LTY400HM07).
The appearance of the power supply
Main features of the device SONY KDL-46EX521:
Installed matrix (LCD panel) LTY460HN02.
The matrix control uses the Timing Controller (T-CON) ESL_C2LV0.4.
To power the backlight, a converter is used, combined with a power supply.
The formation of the necessary supply voltages for all nodes of the SONY KDL-46EX521 TV is carried out by the APS-285 power module, or its analogs.
MainBoard - the main board (motherboard) is a module 1-883-753-32, using microcircuits CXD4727GB, K4B2G1646C-HCH9, KFM2GN6Q2B, Y164B, NJU72040, Sil9287BCNU, GL850G and others.
The CXD2825GA tuner provides TV reception and channel tuning.