Friday 31 January 2020

REPAIR / SERVICING TV PHILIPS 42PFL7403D

Technical description and composition of the PHILIPS 42PFL7403D TV, type of panel and applicable modules. The composition of the modules.
PHILIPS
Model: 42PFL7403D / 10
Chassis / Version: Q529.1E LA
Panel: LC420WF (SA) (A1)
T-CON: 6870C-4200C
Inverter (backlight): integrated into PSU
PWM Inverter: UBA2071AS
MOSFET Inverter: FQPF19N20C
Power Supply (PSU): 310432852763 3104 303 50815B (HJ821.28.B)
PWM Power: 1606B (PFC), UBA2071AS
MOSFET Power: FCP11N60, FQP27P06
MainBoard: 3104.303.51026 - 3104.313.62146
IC MainBoard: CPU: PNX8541E / 2414, PNX5100, EEPROM: M24C64, M24C08, SPI Flash: M25P05, NAND: 512W3A2
Tuner: TD1716F / BHXP-4
Specifications 42PFL7403D
PHILIPS 42PFL7403D
General recommendations for repairing TV LCD
Possible manifestations of defects
- PHILIPS 42PFL7403D does not turn on and does not show any signs of performance at all. Does not blink indicators and does not respond to control buttons.
Typically, with such manifestations, the defect is caused by faulty elements in the main power supply module 310432852763. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches (FCP11N60, FQP27P06) and rectifier diodes in the converters for a short circuit.
In case of diode breakdowns in the secondary circuits, the converter can operate in emergency short-circuit mode without output voltages, and during short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor at the source of the key usually breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback circuits (OOS) of stabilization. PWM controllers (PWM) 1606B (PFC), UBA2071AS, if they do not have visible damage to the case and open fault between the terminals, are usually checked by replacement.
- There is no image, but there is sound and all other functions work. Sometimes when you turn on the image for a second appears and disappears.
These manifestations can be triggered by a power module, or by defects in the inverter, as well as a distortion of the currents in the lamps due to their uneven wear. After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, it is necessary to ring in its converter the power switches for breakdown and the secondary windings of the transformers for an open.
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 TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the 3104.303.51026 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). Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Checking or replacing CPU elements: PNX8541E / 2414, PNX5100, EEPROM: M24C64, M24C08, SPI Flash: M25P05, NAND: 512W3A2 requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by warming up.
If the TV works normally from external devices, but does not tune into television channels, the TD1716F / BHXP-4 tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
Once again, remind users! Attempts at self-repair of a PHILIPS 42PFL7403D TV without the appropriate qualifications and necessary experience can lead to its complete non-repairability!


Service manual and schematic diagram -------------->  PHILIPS 42PFL7403D Chassis Q529.1E LA

 The appearance of MainBoard 3104.303.51026 is shown in the figure below:
3104.303.51026
3104.303.51026 can be used in TVs:
PHILIPS 32PFL7623D/10 (Panel LC320WXN-SAB1 code 136), PHILIPS 32PFL9603D/10 (Panel LK315D3LZ43), PHILIPS 32PFL9613 (Panel 32 ), PHILIPS 37PFL9603D/10 (Panel LC370WUF-SAB1 p/n: 932226169682), PHILIPS 37PFL9603D/10 (Panel LC370WUF SAB1 (LGPH) code 141), PHILIPS 42PFL7403S/60 (Panel p/n: 932225845000), PHILIPS 42PFL7623D/10 (Panel LC420WUE - SAA1), PHILIPS 42PFL9703D/10 (Panel LC420WUF-SAC1), PHILIPS 42PFL9703D/10 (Panel LC420WUF-SAC1 code 143), PHILIPS 42PFL9803H/10 (Panel T420HW02 V.1 code 149 p/n: 932226404682 ).
The appearance of the power supply
Main features of the PHILIPS 42PFL7403D device:
Installed matrix (LCD panel) LC420WF (SA) (A1).
The matrix control uses the Timing Controller (T-CON) 6870C-4200C.
To power the backlight, a converter is used, combined with a power supply, controlled by a UBA2071AS PWM controller. As power elements of the inverter, keys of the type FQPF19N20C are used.
The necessary supply voltages for all nodes of the PHILIPS 42PFL7403D TV are generated by the power supply module 310432852763 or its analogs using 1606B (PFC), UBA2071AS microchips and power switches of the FCP11N60, FQP27P06 type.
MainBoard - the main board (motherboard) is a module 3104.303.51026, using CPU chips: PNX8541E / 2414, PNX5100, EEPROM: M24C64, M24C08, SPI Flash: M25P05, NAND: 512W3A2 and others.
The tuner TD1716F / BHXP-4 provides reception of television programs and tuning to channels.