Friday 6 March 2020

REPAIR / SERVICING TV SONY KDL-32W706B

Technical description and composition of the SONY KDL-32W706B TV, panel type and applicable modules. The composition of the modules.
SONY LED
Model: KDL-32W706B
Chassis / Version: RB2G
Panel: T320HVF04.1
LED driver (backlight): 14STM4250AD-6S01 Rev1.0
PWM LED driver: BD9422EF
MOSFET LED driver: SBR10150CT, TPC8127
Power Supply (PSU): Adapter 19.5V
MainBoard: 1-889-202-22 BAX L
IC MainBoard: CPU: X-Reality PRO CXD4748GB, H5TQ4G83AFR, Nand: TC58NVG3SOFTAIO
Tuner: TUS1-889-203-13
Technical Specifications KDL-32W706B
SONY KDL-32W706B
General repair guidelines for TV LCD LED
Possible malfunctions
- The SONY 32W706B 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.
With such manifestations, in some cases, the Adapter power module is faulty.
The owner of the TV can purchase an external power supply unit such as Adapter and repairing it is not always advisable. In any case, the simplest typical defects characteristic of most IIP schemes can be easily detected and eliminated after opening. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of the power switches of the converters and rectifier diodes for the presence of a possible short circuit.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short-circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key are most often cut off.
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, in the absence of visible damage or explicit short-circuit between the terminals, are checked by replacing 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.
In such cases, the most likely malfunction of the LED backlight elements. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To check the LED lines for breaks without disassembling the panel, for example, a current source will help. It is impossible to open series-connected PN junctions with a simple multimeter, a voltage of the order of several tens of volts is required.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the 1-889-202-22 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). If it is not possible to replace the MB (SSB) card, you need to check the health of its elements - CPU: X-Reality PRO CXD4748GB, H5TQ4G83AFR, Nand: TC58NVG3SOFTAIO. Defective components should be replaced.
If there is no reception of television channels, but the TV is working properly from external devices, first of all it is necessary to check the voltage of the tuner TUS1-889-203-13 and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Owners of the 32W706B TV are recommended for repair only to qualified specialists with the necessary work experience! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!


Service manual / schematic diagram -------------------> SONY Chassis RB2G; MODEL KDL-32W700B, KDL-42W700B, KDL-42W800B, KDL-50W700B, KDL-55W790B, KDL-32W705B, 32W705B, KDL-42W705B, 42W705B, KDL-42W805B, KDL-50W790B, 50W790B, KDL-55W800B, KDL-32W706B, KDL-42W706B, KDL-42W807B, KDL-50W800B, KDL-55W805B, KDL-32W707B, KDL-42W707B, 42W707B, KDL-42W815B, KDL-50W805B, KDL-55W808B, 55W808B, KDL42W817B, 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

 The appearance of MainBoard 1-889-202-22 is shown in the figure below:
1-889-202-22
1-889-202-22 can be used in TVs:
SONY KDL-42W817B (Panel T420HVJ02.1), SONY KDL-42W706B KDL-42W706W (Panel T420HVF06.1), SONY KDL-40W605B (Panel NS4S400DND01 4-528-221-02), SONY KDL-42W705B (Panel T420HVF06.0 xxxxG), SONY KDL-50W817B (Panel T500HVF04.1), SONY KDL-42W828B (Panel T420HVJ02.0), SONY KDL-48W605B (Panel LSY480HN01-001), SONY KDL-32W706B (Panel T320HVF04.1 ).
Main features of the device SONY KDL-32W706B:
Installed matrix (LED-panel) T320HVF04.1.
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 type SBR10150CT, TPC8127 are used.
To power all the internal components of the SONY KDL-32W706B TV, an external adapter type 19.5V is used.
MainBoard - the main board (motherboard) is a 1-889-202-22 module, using CPU chips: X-Reality PRO CXD4748GB, H5TQ4G83AFR, Nand: TC58NVG3SOFTAIO and others.
The TUS1-889-203-13 tuner provides the reception of television programs and tuning to channels.