Technical description and composition of the TOSHIBA 27WL55R TV, type of panel and applicable modules. The composition of the modules.Toshiba
Model: 27WL55R
Panel: V270W1-L04
Lamp backlight: 14 Lamp CCFL
Inverter (backlight): 4H. V0708.001
PWM Inverter: OZ960GN
MOSFET Inverter: FDS8958A
Power Supply (PSU): PD2105 A-2, PD2105 A-1
MainBoard: PD2131, PD2120
IC MainBoard: CPU: FLI8532-LF, EEPROM: M24128BW
Tuner: ENG37A06GF
Control: Service mode: Mute (RC) + MENU (TV)
Specifications 27WL55R
TOSHIBA 27WL55R
General recommendations for repairing TV LCD
Possible manifestations of defects
- The TOSHIBA 27WL55R does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
Most likely, in this case, the main switching power supply (IIP) PD2105 is faulty. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches 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 (OOS) stabilization circuits. PWM controllers (PWM), if they do not have visible damage to the chassis and open short circuit between the terminals, are usually checked by replacement.
- 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.
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 power keys for breakdown and secondary windings of transformers for an open.
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 PD2120 motherboard should begin by checking the stabilizers and power converters needed to power the chips 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: FLI8532-LF, EEPROM: M24128BW. BGA chip malfunctions are usually easy to detect by warming up.
If a tuner ENG37A06GF is suspected of malfunction, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary supply voltage levels and data exchange pulses with the processor via the I2C bus on the corresponding tuner pins.
We recommend the owners of the 27WL55R TV 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!
FIRMWARE FOR SPI FLASH -----------> TOSHIBA 27WL55R , Main: PD2131 , PD2120, Panel: V270W1-L04
The appearance of the MainBoard PD2131 is shown in the figure below:PD2131
PD2131 can be used in TVs:
TOSHIBA 27WL55R (Panel V270W1-L04), TOSHIBA 37WL55R (Panel LC370WX1 (SL)(03)).
Main features of the TOSHIBA 27WL55R device:
Installed matrix (LCD panel) V270W1-L04.
A 4H inverter is used to power the backlight. It is controlled by the OZ960GN PWM controller. As power elements of the inverter, keys of the FDS8958A type are used.
The formation of the necessary supply voltages for all nodes of the TOSHIBA 27WL55R TV is carried out by the PD2105 power module, or its analogues.
MainBoard - the main board (motherboard) is a PD2131 module, using CPU chips: FLI8532-LF, EEPROM: M24128BW and others.
The ENG37A06GF tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: V270W1-L04
Type: a-Si TFT-LCD, Panel
Diagonal size: 27.0 inch
Resolution: 1280x720, WXGA
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 597.12x335.88 mm
Surface: Antiglare (Haze 40%), Hard coating (3H), Reflection 2.0% (Max.)
Brightness: 550 cd / m²
Contrast Ratio: 900: 1
Display Colors: 16.7M (8-bit), CIE1931 75%
Response Time: 8 (G to G)
Frequency: 60Hz
Lamp Type: 14 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V