Technical description and composition of the SONY KDL-32RE403 TV, panel type and applicable modules. The composition of the modules.SONY LED
Model: KDL-32RE403
Chassis / Version: BLM
Panel: IS7S320HN001
LED driver (backlight): 1-981-455-11 173638611 A2194442A
PWM LED driver: BD9423EFV
Power Supply (PSU): Adapter AC / DC 19.5V
MainBoard: 1-981-541-23 173641423 A2222587A
IC MainBoard: CPU: MEDIATEK
Tuner: DE251ZP
Technical Specifications KDL-32RE403
SONY KDL-32RE403
General repair guidelines for TV LCD LED
Possible malfunctions
- The SONY KDL-32RE403 TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
Often in such cases, the Adapter power module is faulty.
The external adapter AC / DC 19.5V power supply is not always subject to repair, especially since the owner can purchase it independently. But, in some cases, it makes sense to open it and eliminate the simple typical defects inherent in converters in pulsed sources. It is necessary to verify the presence of its output voltages and, if they are completely absent, check the power switches and rectifier diodes for a probable short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more 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 the remote control. Or for a second, the image may appear immediately after switching on.
The faulty usually in these cases is the backlight matrix (LED-panel). More often the reason for this is the breakdown of the LEDs, or poor contact in the connectors of the strips, less often the LED driver may be malfunctioning.
To check the LED strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, sometimes you can detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the motherboard 1-981-541-23 should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the CPU elements: MEDIATEK. BGA chip malfunctions are usually easy to detect by warming up.
Before replacing the tuner DE251ZP, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
The appearance of MainBoard 1-981-541-23 is shown in the figure below:1-981-541-23
Main features of the device SONY KDL-32RE403:
The matrix (LED panel) IS7S320HN001 is installed.
The LED driver 1-981-455-11 is used to power the backlight LEDs, it is controlled by the BD9423EFV PWM controller.
To power all the internal nodes of the SONY KDL-32RE403 TV, an external adapter type AC / DC 19.5V is used.
MainBoard - the main board (motherboard) is a module 1-981-541-23, using CPU chips: MEDIATEK and others.
The DE251ZP tuner provides television reception and channel tuning.