Monday 9 March 2020

REPAIR / SERVICING TV SONY KDL-46HX855

Technical description and composition of the SONY KDL-46HX855 TV, panel type and applicable modules. The composition of the modules.
SONY LED
Model: KDL-46HX855
Chassis / Version: AZ3F CHASSIS
Panel: FQLR460LT01
T-CON: 1P-111CJ00-4010 PYL2 (SM4109, 25Q32)
LED driver (backlight): ST4046RD-S01
PWM LED driver: AN37011B
Power Supply (PSU): APS-324 1-886-217-1
PWM Power: MIP2H2, CXD9969AP
MainBoard: 1-885-388-52
IC MainBoard: CXD4727GB, K4B2G1646C-HCH9, KFM4G16Q4B, SIL9287BCNU, GL850G, D2826ER, TPA6138, PS54425
Technical Specifications KDL-46HX855
SONY KDL-46HX855
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The SONY KDL-46HX855 TV does not turn on and does not show any signs of operability at all. There is no reaction to the remote control and control buttons from the front panel.
Failure in such cases should begin to be sought in the APS-324 power supply circuits. It is necessary to measure its output voltages, and in case of their absence, check the operability of the power switches of the converters and rectifier diodes for the probability of a short circuit.
In the event of breakdowns in the secondary circuits of the converter, it can usually fail in short circuit mode, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse or current sensor at the source of the key most often breaks.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers MIP2H2, CXD9969AP, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, but there is sound, it reacts to the remote control. Or the image appears when you turn on and immediately disappears
The most likely in these cases is a malfunction of the LED backlight. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required. Then it is necessary to open the panel and check each LED separately with a multimeter. If the capabilities of your multimeter do not allow you to open the LED in the forward direction or dual LEd are used, then the PN junction of the emergency zener diode can indirectly serve as a health indicator. In case of LED-a failure, the zener diode PN junction will either be cut off or broken into short-circuit.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the 1-885-388-52 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).
Once again, remind users! Attempts to self-repair a SONY KDL-46HX855 TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
1. Service Manual 153 pages of 2012 FOR  the KDL-40HX850, KDL-40HX853, KDL-40HX855, KDL-46HX850, KDL-46HX853, KDL-46HX855, KDL-55HX850, KDL-55HX853.

Service manual -------------->  Sony KDL40/40/55HX850/853/855 Chassis AZ3F

 2. Service Manual with Schematic Diagram --------------->  59 pages of 2012 FOR the models KDL-26EX555, KDL-32EX555, KDL-32EX655, KDL-32HX755, KDL-40EX655, KDL-40HX752, KDL-40HX755, KDL-46EX655, KDL-46HX2 KDL-46HX755, KDL-46HX855, KDL-55HX755, KDL-55HX855.

 

 The appearance of MainBoard 1-885-388-52 is shown in the figure below:
1-885-388-52
The appearance of the power supply
Main features of the device SONY KDL-46HX855:
Installed matrix (LED-panel) FQLR460LT01.
The matrix control uses the Timing Controller (T-CON) 1P-111CJ00-4010.
The LED driver ST4046RD-S01 is used to power the backlight LEDs, it is controlled by the AN37011B PWM controller.
The formation of the necessary supply voltages for all nodes of the SONY KDL-46HX855 TV is carried out by the APS-324 power module, or its analogs using MIP2H2, CXD9969AP chips.
MainBoard - the main board (motherboard) is a module 1-885-388-52, using microcircuits CXD4727GB, K4B2G1646C-HCH9, KFM4G16Q4B, SIL9287BCNU, GL850G, D2826ER, TPA6138, PS54425 and others.