Monday, 30 December 2019

REPAIR / SERVICING TV SAMSUNG LW15M23CP

Technical description and composition of the SAMSUNG LW15M23CP TV, panel type and applicable modules. The composition of the modules.
SAMSUNG
Model: LW15M23CP
Chassis / Version: VE15EO
Panel: 15 inch 1024x768
Lamp backlight: 4 Lamp CCFL
Inverter (backlight): integrated into PSU BN41-00347A
PWM Inverter: OZ960
MOSFET Inverter: FDS4935
Trans Inverter: TMP90199CT, NTMD6N03R2
Power Supply (PSU): BN44-00112A
PWM Power: NCP1200P60
MOSFET Power: P6NK60ZFP
MainBoard: BN41-00641A REV: MP1.0
IC MainBoard: TDA15021H / N1B80, AT24C16AN, TDA7266D, TSU396QWJ A6MC108999H, TDA7050, FAN7311, MP1410ES
Tuner: BN40-00077A
Control: RC: BN59-00437A
Technical Specifications LW15M23CP
SAMSUNG LW15M23CP
General repair guidelines for TV LCD
Possible malfunctions
- SAMSUNG LW15M23CP TV 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.
In some of these cases, a fault is detected in the BN44-00112A power module. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of the power switches of the converters and rectifier diodes for the presence of a possible short circuit.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key are most often cut off.
Mos-Fet power switches used in switching power supplies sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible key parameters. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers NCP1200P60, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new, or obviously working.
- There is no image, there is sound, it responds to the remote. Or the image may appear for a second when turned on and immediately disappears.
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 for 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.
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 indicator blinks or glows constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the BN41-00641A motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, you should update or replace the software (software). In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its chips TDA15021H / N1B80, AT24C16AN, TDA7266D, TSU396QWJ A6MC108999H, TDA7050, FAN7311, MP1410ES and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
Before replacing the tuner BN40-00077A, 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
We recommend the owners of the LW15M23CP TV for repair only to qualified specialists with the necessary work experience! Attempts to repair it yourself without the appropriate knowledge and skills can lead to irreversible negative consequences!

Service manual and schematic diagram SAMSUNG LW15M23CP Chassis VE15EO.
PSU Samsung BN44-00112A Power supply.

 The appearance of the MainBoard BN41-00641A is shown in the figure below:
BN41-00641A
BN41-00641A can be used in TVs:
SAMSUNG LE15S51BP LE15S51 (Panel 15 inches 1024x768), SAMSUNG LW15M23CP (Panel 15 inches 1024x768), SAMSUNG LW20M21CPX LW20M21BWT (Panel HT201V01-101).
The appearance of the power supply
Main features of the SAMSUNG LW15M23CP device:
Installed matrix (LCD panel) 15 inches 1024x768.
To power the backlight, a converter is used, combined with a power supply, controlled by the OZ960 PWM controller. The transformer TMP90199CT, NTMD6N03R2 is installed in the inverter converter. As power elements of the inverter, keys of the FDS4935 type are used.
The necessary supply voltages for all nodes of the SAMSUNG LW15M23CP TV are generated by the BN44-00112A power module or its analogs using NCP1200P60 microcircuits and P6NK60ZFP power switches.
MainBoard - the main board (motherboard) is a BN41-00641A module, using TDA15021H / N1B80, AT24C16AN, TDA7266D, TSU396QWJ A6MC108999H, TDA7050, FAN7311, MP1410ES chips, and others.
The tuner BN40-00077A provides the reception of television programs and tuning to channels.