Technical description and composition of the TOSHIBA 19AV733 TV, type of panel and applicable modules. The composition of the modules.Toshiba
Model: 19AV733
Panel: M185B1-L03
Inverter (backlight): 715G3721-P02-H20-001U
Power Supply (PSU): 715G3721-P02-H20-001U
MainBoard: 715G3748 - M01-000-005X
Tuner: ENV57S01D8RF
Specifications 19AV733
TOSHIBA 19AV733
General recommendations for repairing TV LCD
It is advisable to start repairing the TOSHIBA 19AV733 TV with an external examination of all its constituent elements, both internal electronic components and external. Inspection is also subject to body elements, control buttons, screen, connectors and cords. Often, by the external signs and nature of some damage, it is possible to draw preliminary conclusions and determine a further algorithm for troubleshooting. Experienced repairmen are often aware of the causes of the defect and possible consequences, for example, from ring cracks in the soldering of the leads of the elements, as well as from swollen capacitors or resistors burnt to coal dust and other external indirect signs.
If the power supply module 715G3721-P02-H20-001U malfunctions, the external manifestations may be different, for example, the TOSHIBA 19AV733 does not turn on at all and there is no indication of the indicator lights on the front panel. When diagnosing and repairing the power supply, first of all, it is necessary to check the fuse and, if it is broken, it is necessary to identify the cause. Often in such cases, an avalanche (thermal) breakdown is detected in the power semiconductor elements of the module - rectifier diodes or power key.
It should be remembered that the N-FET keys used in flyback converters rarely fail for no reason that must be sought by checking other elements of the circuit. Often the breakdown is caused by malfunctions of electrolytic capacitors or semiconductor elements in the primary circuit, or by a break in the resistors in the stabilization circuits. The PWM controller chip can also cause a breakdown of the power switch of the converter.
It is somewhat more difficult to look for a malfunction in the converter of the power module with an active KKM (power factor corrector).
If the TOSHIBA 19AV733 TV does not have an image, but there is sound, the malfunction should be sought in the backlight lamp power converter (inverter). It is also necessary to check the serviceability of the electrolytic capacitors of the filter of the secondary rectifiers of the PSU (power supply) for an overstated ESR.
When repairing the inverter 715G3721-P02-H20-001U, it is often necessary to disable the protection for diagnostics, which, for the purpose of fire safety, turns it off in any emergency situation, for example, during a malfunction or uneven wear of the lamps, which makes it difficult to find a defect.
It should be remembered that when the protection is turned off, there is always a risk of failure of the power elements of the inverter during diagnosis. After repair, it is necessary to restore all standard converter protection circuits.
If the motherboard 715G3748-M01-000-005X is faulty, first of all it is necessary to check all the linear power regulators of its chips and, if necessary, update the software. Sometimes you can check the health of MB only by replacement.
If you suspect a malfunction of the ENV57S01D8RF tuner, first of all, you need to make sure that the voltage of the varicaps (30-33V) is present on the corresponding output of the tuner, as well as other voltage supplying it.
Remember! Attempts to self-repair by users of the TOSHIBA 19AV733 TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 19/22AV733R
Service Manuals with Schematic Diagrams 29 pages on model 19AV733G, 19AV734G.
The appearance of the MainBoard 715G3748 is shown in the figure below:715G3748
715G3748 can be used in TVs:
TOSHIBA 19AV733 (Panel M185B1-L03), TOSHIBA 22AV733R 22AV734R (Panel V216B1-L02 RevC1).
Main features of the TOSHIBA 19AV733 device:
Installed matrix (LCD panel) M185B1-L03.
To power the backlight used inverter 715G3721-P02-H20-001U.
The formation of the necessary supply voltages for all nodes of the TOSHIBA 19AV733 TV is carried out by the power module 715G3721-P02-H20-001U, or its analogues.
MainBoard - the main board (motherboard) is a 715G3748 module.
The ENV57S01D8RF tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: M185B1-L03
Type: a-Si TFT-LCD, Panel
Diagonal size: 18.5 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 409.8x230.4 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 300 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 72%
Response Time: 1.3 / 3.7 (Tr / Td)
Frequency: 60Hz
Lamp Type: 2 pcs CCFL Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V