Saturday, 25 January 2020

REPAIR / SERVICING TV PHILIPS 32PF9956

Technical description and composition of the PHILIPS 32PF9956 TV, panel type and applicable modules. The composition of the modules.
PHILIPS
Model: 32PF9956 / 12
Chassis / Version: FTL3.1E AA
Panel: LQ315T3LZ13
T-CON: X3219TPZ B
Inverter (backlight): RDENC2158TPZZ, QKITS0055SNE4
Power Supply (PSU): 3104-313-60094, 3104 328 29521-02
PWM Power: MC43067P, AVS1ACP08 (stby)
MOSFET Power: STP15NK50ZFP
MainBoard: 3104-313-60126A 3104 303 38206A
IC MainBoard: PNX8550EH, SIL9993CTG100, TC58DVM92F1TGI0
Tuner: UV1318S / A I HN-3
Control: IR: 3104 328 32472
Specifications 32PF9956
PHILIPS 32PF9956
General recommendations for repairing TV LCD
Possible malfunctions
- The PHILIPS 32PF9956 TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light or flash.
In such cases, the malfunction should be sought first in the power supply module 3104-313-60094. It is necessary to verify the presence of its output voltages and, if they are completely absent, check the power switches (STP15NK50ZFP) and rectifier diodes for a probable short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during a short circuit in the elements of the primary circuit, the mains fuse usually 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) MC43067P, AVS1ACP08 (stby), in the absence of external damage and a 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 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.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- 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 3104-313-60126A 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). In cases of attempts to repair the MB board (SSB), it is necessary to check the serviceability of its elements - PNX8550EH, SIL9993CTG100, TC58DVM92F1TGI0 which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
Before replacing the UV1318S / A I HN-3 tuner, if there is no tuning for the channels, 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
Attention TV owners! Attempts at self-repair of PHILIPS 32PF9956 are not recommended by the manufacturer and can lead to serious negative consequences!


Service manual and schematic diagram    ------------->  PHILIPS 32PF9956 Chassis FTL3.1E AA.

 The appearance of the MainBoard 3104-313-60126A is shown in the figure below:
3104-313-60126A
The appearance of the power supply
Main features of the PHILIPS 32PF9956 device:
Installed matrix (LCD panel) LQ315T3LZ13.
The matrix control uses the Timing Controller (T-CON) X3219TPZ.
The RDENC2158TPZZ inverter is used to power the backlight.
The necessary supply voltages for all nodes of the PHILIPS 32PF9956 TV are generated by the power supply module 3104-313-60094, or its analogs using microcircuits MC43067P, AVS1ACP08 (stby) and power switches of the STP15NK50ZFP type.
MainBoard - the main board (motherboard) is a module 3104-313-60126A, using chips PNX8550EH, SIL9993CTG100, TC58DVM92F1TGI0 and others.
The UV1318S / A I HN-3 tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: SHARP
Model: LQ315T3LZ13
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1366x768, WXGA
Display Mode: Normally Black, Transmissive
Active Area: 697.343x392.064 mm
Surface: Antiglare (Haze 23%), Hard coating (2H), Antireflection
Brightness: 500 cd / m²
Contrast Ratio: 800: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 15 (Tr + Td)
Frequency: 60Hz
Lamp Type: 16 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V