Saturday 7 March 2020

REPAIR / SERVICING TV SONY KDL-40V2500

Technical description and composition of the SONY KDL-40V2500 TV, panel type and applicable modules. The composition of the modules.
SONY
Model: KDL-40V2500
Chassis / Version: WAX2T
Panel: 720p HD
Inverter (backlight): PCB2676 - A06-126268 G & PCB2677 - A06-126269
Power Supply (PSU): 1-871-504-11 - A1207096B
PWM Power: A1207096A CXD9841P, MIP2H2, FA5501AN (PFC)
MainBoard: 1-871-991-21
IC MainBoard: CPU: NEC D61123F1 100, NAND: HYNIX HY27US08281A; CFE-050-FEE-08 1-869-656-21
Tuner: BDT-HF441Z 8-597-598-00 CFE-050-TUE-08 1-869-657-12
Technical Specifications KDL-40V2500
SONY KDL-40V2500
General recommendations for repairing TV LCD
An external examination of the external and internal elements should be carried out in a timely manner before the start of operations for their dismantling. Often, based on certain external signs, it may be possible to draw certain conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. Electrolytic capacitors of filters with a swollen case, as well as ring cracks or a layer of coal on burned-out resistors formed in the soldered terminals of the heating elements, sometimes tell the repairman the causes of the malfunction and possible consequences.
A malfunction of the power supply is often manifested corny - the TV does not turn on, does not make any sounds, does not light up and does not blink with any indicators. Diagnostics and repair of the common power supply should always begin with a check of the mains fuse and the condition of the electrolytic capacitors of the secondary rectifier filters. Defective and swollen capacitors should be replaced with new ones. If the fuse breaks, it is advisable to check for a breakdown, first of all, all the power semiconductor elements of the converter and the diode bridge of the rectifier network, as well as the large electrolytic capacitor of the filter of the rectifier network.
If a breakdown of the power switch is detected, it should be remembered that in a switching power supply (IIP) it does not fail by itself without any reasons that should be sought by checking other elements of the primary circuit - electrolytic capacitors, a PWM controller, which can only be checked replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
If the SONY KDL-40V2500 TV does not have an image, but there is sound, the malfunction should be sure that the backlight power converter (inverter) is working properly. It is also necessary to check the electrolytic capacitors of the filter of the secondary rectifiers of the BP (power supply) for excessive ESR. When diagnosing a malfunction of the inverter with the protection off, special precautions must be taken, because there is a risk of failure of the power elements of the inverter. After diagnosis, it is imperative to restore the protection circuits for the inverter to operate normally.
On the motherboard 1-871-991-21, in case of a malfunction, you should first check the performance of all the stabilizers and power converters of the microcircuits, and also, if necessary, update the software (software). When repairing an MB board, you must check its CPU components: NEC D61123F1 100, NAND: HYNIX HY27US08281A; CFE-050-FEE-08 1-869-656-21. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
If there is no reception of television channels, but the TV works correctly from external devices, first of all, check the voltage of the tuner BDT-HF441Z 8-597-598-00 CFE-050-TUE-08 1-869-657-12 and update the software.
Attention! For users and owners of KDL-40V2500 TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.


Service manual / schematic diagram --------------->   SONY KDL-40V2500 KDL-46V2500 KDL-46V25L1 CHASSIS WAX2F


 The appearance of MainBoard 1-871-991-21 is shown in the figure below:
1-871-991-21
1-871-991-21 can be used in TVs:
SONY KDL-46S2530 (Panel LTY460WT-LH3), SONY KDL-40V2500 (Panel 720p HD).
The appearance of the power supply
Main features of the device SONY KDL-40V2500:
Installed matrix (LCD panel) 720p HD.
A PCB2676 inverter is used to power the backlight.
The necessary supply voltages for all nodes of the SONY KDL-40V2500 TV are generated by the power module 1-871-504-11, or its analogs using the A1207096A CXD9841P, MIP2H2, FA5501AN (PFC) microcircuits.
MainBoard - the main board (motherboard) is a module 1-871-991-21, using CPU chips: NEC D61123F1 100, NAND: HYNIX HY27US08281A; CFE-050-FEE-08 1-869-656-21 and others.
The tuner BDT-HF441Z 8-597-598-00 CFE-050-TUE-08 1-869-657-12 provides the reception of television programs and tuning to channels.