Technical description and composition of the TOSHIBA 37AV502PR TV, type of panel and applicable modules. The composition of the modules.Toshiba
Model: 37AV502PR
Chassis / Version: PE0484
Panel: LC370WXN (SA) (C2) 75012583
T-CON: 75013094
Inverter (backlight): 37 VT-Y 75013079
PWM Inverter: BD9897FS (32H)
Power Supply (PSU): PE0531
PWM Power: A6169 (8), STR-Z2589, 2A20112 (PFC)
MOSFET Power: P10NK80, 10N60
Mainboard: PE0484
IC MainBoard: CPU: TDA8891; Scaler: TDA15451;
Tuner: TAEA-G081D
Specifications 37AV502PR
TOSHIBA 37AV502PR
General recommendations for repairing TV LCD
It is advisable to start the diagnosis of a malfunction of the TOSHIBA 37AV502PR TV, like all others, with an external examination of possible changes, both external and internal elements. Often, for certain external signs, the repairman can draw some 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. 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.
In the case when the 37AV502PR does not turn on, does not respond to the remote control and buttons on the front panel, does not blink bulbs and does not show any signs of operability, most likely in this case the power module is faulty. In this case, the diagnosis and repair of the common power supply should always be started by checking the mains fuse. When it breaks, it is advisable to check for a breakdown, first of all, all 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 and the key transistor 8447L.
Power switches in flyback converters fail extremely rarely for no reason and, if they are broken, it is necessary to look for a malfunction in the stabilization circuits by checking electrolytic capacitors, semiconductor devices, and resistors in the primary circuit. The reason may be a malfunction of the PWM controller chip 10393 816K, which can only be checked by replacing with a new or obviously working one.
If the power module uses an active KKM circuit (power factor control), troubleshooting is somewhat more complicated.
Sometimes the TOSHIBA 37AV502PR TV does not have an image, but there is sound, or the image appears and immediately disappears. In this case, there is a high probability of a malfunction of the backlight converter, or of the lamps themselves, which can be checked by replacement. In such cases, it is necessary to verify the serviceability of all electrolytic capacitors of the filter according to the power supply of the inverter itself, including in the power supply unit (power supply unit).
Repair of the inverter 37 VT-Y 75013079 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 to be able to make the necessary measurements at the control points of the circuit.
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.
For owners of the 37AV502PR TV, we recommend that you contact qualified professionals with experience to repair! Self-repair attempts without the appropriate knowledge and skills can lead to serious negative consequences!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 37AV502PR. Service manual and schematic diagram
Service Manuals with Schematic Diagrams 84 pages of 2008 on model 37AV502PR, 42AV502PR
The appearance of MainBoard PE0484 is shown in the figure below:PE0484
PE0484 can be used in TVs:
TOSHIBA 32AV500PR (Panel LC320WXN (SB)(B1)), TOSHIBA 32AV500PSR (Panel LC320WXN (SB)(B1)), TOSHIBA 32AV501PR (Panel LK315T3LA31), TOSHIBA 32AV502PR (Panel LK315T3LA31 (75012574)), TOSHIBA 37AV502PR (Panel LC370WXN(SA)(C2) 75012583), TOSHIBA 42AV500PSR (Panel LC420WXN (SA)(B1)), TOSHIBA 42AV501PR (Panel LC420WX7-SLC1), TOSHIBA 42AV502PR (Panel LC420WXN-SAB1), TOSHIBA 37AV500PR (Panel AX094B002B).
PSU Advanced
The PE0531 power module is made using the Power Factor Correction (PFC) scheme to eliminate multiple AC harmonics introduced into the power supply by the device. The PFC assembly is a Step-Up Converter based on a 2A20112 PWM controller that evenly distributes high-frequency impulses of the charging current of the electrolytic capacitor of the rectifier filter of the mains voltage over a period of 50 Hz. The current of its charge in this case will already be determined not by its reactance (usually 10-30 ohms for the network frequency), but by the elements of the converter. As a result, a change in the amplitude of the pulses (envelope) of the consumed current of the converter will repeat the shape and phase of the input sinusoidal voltage. The availability of an increased voltage (about + 380V) in the operating mode on the capacitor of the line filter indicates the serviceability of the PFC node.
The appearance of the power supply
Main features of the TOSHIBA 37AV502PR device:
Installed matrix (LCD panel) LC370WXN (SA) (C2) 75012583.
The matrix control uses the Timing Controller (T-CON) 75013094.
Inverter 37 is used to power the backlight, controlled by the BD9897FS PWM controller (32n).
The necessary supply voltages for all nodes of the TOSHIBA 37AV502PR TV are generated by the PE0531 power module or its analogs using A6169 (8), STR-Z2589, 2A20112 (PFC) microcircuits and power switches of the type P10NK80, 10N60.
MainBoard - the main board (motherboard) is a PE0484 module using CPU chips: TDA8891; Scaler: TDA15451; and others.
The TAEA-G081D tuner provides TV reception and channel tuning.
TOSHIBA 37AV502PR LCD TV with LC370WXN (SA) (C2) LCD, 37 "(94 cm) diagonal size 16: 9. The ratio of maximum brightness to minimum (contrast) is 850: 1. Dynamic contrast ratio of 14000: 1 is achieved special control of the backlight operation. You can view images in high quality HD at a resolution of 1366x768 pixels in the standard for graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation takes place in st andarts 480i, 480p, 576i, 576p, 720p, 1080i.
The power of the sound system 20 W (2x10 W) provides 4 speakers. The audio processing system NICAM STEREO is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x3, component, SCART x2, RGB, HDMI x2. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768.
The power consumed by the TV in the operating mode from the network is 164 watts.
Overall dimensions: with stand 913x619x247 mm, without stand 913x579x107 mm.
TV Weight: with stand: 16.2 kg, without stand: 14.9 kg.
Attention! The TOSHIBA 37AV502PR LCD TV panel LC370WXN (SA) (C2) 75012583 is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!