
PHILIPS
Model: 26PF9946 / 12
Chassis / Version: LC4.2E AA
Panel: LC260W01-A5K8 // (a5 (ka) (A5) (K6)
Inverter (backlight): 6632L-0053 Y 2300KFG018C-F YPNL-M012C
Power Supply (PSU): PLCD170P1 (23081)
MainBoard: 3139-123-5804.2 WK415.1
IC MainBoard: CPU: TDA12029H; DRAM: K4D263238M-QC50;
Tuner: UR1316 / A I H-3
Specifications 26PF9946
PHILIPS 26PF9946
General recommendations for repairing TV LCD
Like all other televisions, it is advisable to start PHILIPS 26PF9946 / 12 with a careful inspection of both external and internal elements and modules. Often, by visible changes, it is possible to determine the further direction of troubleshooting and localization of the defect before the start of the acquisition of oscillograms and the necessary measurements. Ring cracks in the soldering of the leads of the heating elements, swollen electrolytic capacitors, a charred paint layer on the resistors - all this for the repairman can be a hint in the assumptions about the causes and consequences of the malfunction.
Power Module Repair
Sometimes the PHILIPS 26PF9946 / 12 TV simply does not turn on. No control lights on the front panel are lit or blinking, the TV does not respond to the remote control and does not make any sounds or any signs of life when turned on. The most likely cause of the malfunction is the failure of the PLCD170P1 (23081) common power module. In the absence of swollen filter capacitors of the secondary rectifiers, the diagnostics of the power supply should always be started by checking the fuse and, if it is broken, it is first necessary to check the rectifier bridge diodes and the power switch for the possibility of an avalanche or thermal breakdown.
In most cases, a breakdown of the N-Fet converter key does not occur for no reason and you should look for other faulty circuit elements that could provoke a defect. This can be dried electrolytic capacitors in the primary circuit, and faulty damper elements, as well as dangling resistors or punched semiconductor elements in the stabilization circuits. Possible defective PWM chip from the manufacturer.
In cases where the Power Factor Corrector (PFC) is used in the power supply, troubleshooting can be a bit more complicated.
Inverter Repair
If the PHILIPS 26PF9946 / 12 does not have an image, but there is sound, there is a possibility of a malfunction of the backlight or power converter. You should also make sure that the electrolytic capacitors of the secondary rectifiers of the common power supply are working.
Repair of the inverter 6632L-0053 Y 2300KFG018C-F YPNL-M012C can often be somewhat complicated by the use of special protection circuits, which are designed to disconnect it in emergency cases for fire safety when the lamps are depressurized, or short circuits or breaks in high-voltage circuits and connections. Sometimes it becomes necessary for diagnostic purposes to block the protection circuits in order to be able to make the necessary measurements at the control points of the circuit.
When diagnosing with the protection off, special precautions must be taken, because there is a risk of failure of the power elements of the inverter. After the diagnosis, it is imperative to restore the protection circuits for the inverter to operate normally.
Repair Main Board
Repair of the SSB motherboard must begin with the diagnosis and verification of all linear stabilizers or power converters of its microcircuits. Sometimes it may be necessary to update the software (software) - flashing FLASH or EEPROM.
It should be remembered! Attempts to repair the PHILIPS 26PF9946 / 12 TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
Service manual and schematic diagram 26PF9946/12 Chassis LC4.2E AA
MODELS 17PF9946/12, 23IF9946/12, 23PF9956/12, 23PF9946/12, 26PF9956/12, 26PF9320/10, 26PF8946/12, 26PF9946/12

3139-123-5804.2
3139-123-5804.2 can be used in televisions:
PHILIPS 23PF9956/12 (Panel LC230W01-A2 K8), PHILIPS 26PF9946/12 (Panel LC260W01-A5K8), PHILIPS 32PF9946/12 (Panel LC230W01-A2K8).
The appearance of the power supply
Main features of the PHILIPS 26PF9946 device:
The matrix (LCD panel) LC260W01-A5K8 or (a5 (ka) (A5) (K6) is installed.
To power the backlight used inverter 6632L-0053.
The necessary supply voltages for all nodes of the PHILIPS 26PF9946 TV are generated by the PLCD170P1 power supply module, or its analogs.
MainBoard - the main board (motherboard) is a module 3139-123-5804.2, using CPU chips: TDA12029H; DRAM: K4D263238M-QC50; and others.
The tuner UR1316 / A I H-3 provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG.Philips LCD
Model: LC260W01-A5K8
Type: a-Si TFT-LCD, Panel
Diagonal size: 26.0 inch
Resolution: 1280x768, WXGA
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 566.4x339.84 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 450 cd / m²
Contrast Ratio: 500: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 7.5 / 8.5 (Tr / Td)
Frequency: 60Hz
Lamp Type: 14 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 20 pins
Voltage: 12.0V