I have a JWIN JV-DTV37 LCD TV. The Stand By led is red, after become green for 5 seconds and after red again. The power board do not have 24V and 12 V. The 5 VCC is present. I need the manual service. and circuit diagram of Power Board A1T4L37PN00

hi could be bad capacitors in the psu board,thanks

shaun

Hello Sagar,
green led means tv powered on and status ok.
Red blinking light almost always means defect, overcurrent or overload.
6 blinks for Sony lcd flat tv means trouble in backlight circuit, or backlight inverter (backlight illumination or lighting makes your tv screen visible).
common problems in the inverter circuit, which drives the backlight, or shorted drivers, or short-circuit transformers or open circuits.
You should find the problem in the inverter circuit, or in the power supply board or in the main board.
Also look for bad capacitors (electrolytic caps) which are bulged and swollen on top.
Decoupling plugs from printed circuit boards can help you in finding the problem board by elimination method.
If you power up the set after unplugging certain plugs on f.e. the inverter board , this could result in getting a green power led and concluding that this board is faulty.

succes,
Walter from Antwerp, Belgium.

Problem is related with Back light error. Check 24V DC from power board to inverter board. if ok then Inverter board or LCD Panel needs to be replace.

A TV nor turning on is most likely caused by a faulty power supply or main board. Are you intending to fix the set yourself?

All the caps look good (bad cap can look normal but can have high ESR)?
Are you getting PS_ON from the main board to turn on the 12/24vdc power supply section?
It may have sensed shorted or over current draw so it tsays it shutdown mode. Try disconnecting the power cables to the inverter board to see if the 12/24v will come back.
Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors pictures: http://s807.photobucket.com/albums/yy352/budm
Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague
Parts: www.shopjimmy.com
Parts: http://interliquidparts.com/

Capacitors kit: http://lcdalternatives.auctivacommerce.com/Default.aspx he can make you a set of caps.
Or www.digikey.com, just make sure to use caps with low ESR, 105c, high ripple current and long life rating such as PANASONIC FM or FC series.

Power LED Blinking timing chart
When an abnormality has occurred the unit, the protection circuit operates and reset to the stand by mode. At this time, the defective block can be identified by the number of blinks of the Power LED on the front panel of the unit.
blinking

1 dg board, (stv 5v sense time out)
2 d board
3 d board
4 p board
5 d board
6 su sd sc boards
7 su sd sc boards
8 ss board
9 panel config
10 digi board-
11 pb board
12 h board
13 dg board

Tom Miller
Broadcast Eng

Error Indication Information
Error No. Error Information ERROR DESCRIPTION LAMP LED OSD LAMP OFF
(Note 3) (Note 4)
POWER LED TEMP LED
Note:
1.When any of the above errors has occurred, the LED will flash as shown above every 5 seconds.
2.When two or more errors have occurred at the same time, the LED will light up or flash as shown above, and then
change to another every 5 seconds in turn.
3.Warning OSD appears when the Air Filter is clogged 90%, accumulated operation time of the Lamp reaches 5000 hours,
or accumulated operation time of the Air Filter reaches 400 hours.
4.LAMP OFF: The LED will flash right after the Lamp goes off.
5.IC2301 is mounted on LCD Main C.B.A. which is included in the Projection Unit.
6.IC6001 is mounted on TV Main C.B.A.
Clogged air filter
more than 90%
15)
16)
17)
18)
1)
2)
3)
4)
5)
6)
7)
11)
8)
9)
10)
12)
13)
14)
- flashes 5 times -
every 5 seconds
IC2301(pin82) detects the clogged air filter, then indicates the
error when the air filter is clogged 90%.
Front Fan stop or
Lamp Fan stop
flashes orange
once every
5 seconds
- -
IC2301(pin12) detects the Front FAN stop or Lamp
FAN stop, then indicates the error when the Front FAN
or Lamp FAN is stopped.
Lamp Cover open
Temperature Sensor
short or open
flashes orange
twice every
5 seconds
flashes orange
3 times every
5 seconds
flashes green for
140 seconds.
flashing red for
60 seconds.
light up red.
flashes once
every 5 seconds
flashes once
every 5 seconds
flashes red for
10 minutes
flashes once
every 5 seconds
-
-
-
-
Abnormal
Temperature
flashes twice
every 5 seconds
flashes twice
every 5 seconds
- -
Request for Lamp
Replacement - - lights up
Power Ballast Error
(abnormal
Lamp voltage)
- -
flashes 3 times
every 5 seconds
Power Ballast Error
(abnormal
temperature)
- -
flashes 4 times
every 5 seconds
Power Ballast Error
(other causes) - -
- -
Request for Filter
Cleaning -
Abnormal Voltage
on 16 V line of
LCD Main C.B.A.
-
flashes twice
every 5 seconds
flashes twice
every 5 seconds
Abnormal Voltage
on 14 V line of
LCD Main C.B.A.
-
flashes 3 times
every 5 seconds
flashes 3 times
every 5 seconds
Abnormal Voltage
on 7 V line of
LCD Main C.B.A.
-
flashes 4 times
every 5 seconds
flashes 4 times
every 5 seconds
IC2301(pin76) detects the Lamp Cover Unit condition
(open or close), then indicates the error when the
Lamp Cover Unit is open.
IC6001(pin85) detects the Duct FAN stop, then
indicates the error when the Duct FAN is stopped.
IC2301(pin74 and 75) detects open or short of the Temperature
Sensor (R2911) on Front Thermistor C.B.A., then indicates the
error when Temperature Sensor is open or shorted.
(The error is not detected for 1 minute after Lamp ON.)
IC2301(pin74 and 75) detects the temperature attached near
the Front FAN by the Temperature Sensor (R2911) on Front
Thermistor C.B.A., then indicates the error when the
temperature becomes more than 43 C (109 F).
(The error is not detected for 1 minute after Lamp ON.)
IC6001(pin86 and 87) detects open or short of the
Temperature Sensor (R2901) on Lamp Thermistor C.B.A.,
then indicates the error when Temperature Sensor is open or
shorted.
(The error is not detected for 4 minutes after Lamp ON.)
IC2301(pin74 and 75) detects the temperature attached near
the Lamp by the Temperature Sensor (R2901) on Lamp
Thermistor C.B.A., then indicates the error when the
temperature becomes more than 60 C (140 F).
(The error is not detected for 4 minutes after Lamp ON.)
IC2301(pin11) detects the error of LCD Power C.B.A.,
then indicates the error when the temperature fuse
(117 C)(243 F) in LCD Power C.B.A. is open.
IC2301(pin11) detects the error of LCD Power C.B.A. and Lamp,
then indicates the error when an inner malfunction of LCD Power
C.B.A. occurs, the Lamp voltage becomes more than 130V or
less than 30V, Lamp current becomes more than 5A, or the Lamp
is cracked.
IC2301(pin11) detects the error of the Lamp, then indicates the
error when the Lamp is short-circuit.
IC2301(pin48) detects +16V line voltage on LCD Main
C.B.A., then indicates the error when the voltage
becomes less than +13V.
IC2301(pin47) detects +14V line voltage on LCD Main
C.B.A., then indicates the error when the voltage
becomes less than +11V.
IC2301(pin45) detects +7V line voltage on LCD Main
C.B.A., then indicates the error when the voltage
becomes less than +5.7V.
IC2301(pin44) detects +3.3V line voltage on LCD Main
C.B.A., then indicates the error when the voltage
becomes less than +2.5V.
flashes 3 times
every 5 seconds
flashes 4 times
every 5 seconds
Abnormal Voltage
on 3.3 V line of
LCD Main C.B.A.
-
-
-
- flashes 5 times
every 5 seconds
Forced cooling
The failure of Lamp
light up
-
Temperature Sensor
short or open
-
-
Abnormal
Temperature
Duct Fan stop -
When accumulated operation time of the the Lamp reaches
5000 hours, OSD (replacing the Lamp) appears on the screen.
Note: The Lamp time is stored in EEPROM (IC2305).
When accumulated operation time of the Air Filter reaches 400
hours, OSD (cleaning the Air Filter) appears on the screen.
Note: The Filter time is stored in EEPROM (IC2305).
During forced cooling, this indication is indicated.
IC2301 (pin11) detects the failure of light up processing of
the Lamp, then the POWER LED is changed as follows.
1) POWER LED flashes green for 140 seconds (while turning on).
2) POWER LED flashes red for 60 seconds (while cooling).
3) POWER LED lights up red (standby).
Note: If the Lamp will not light after attempting turning on the
power 2 or 3 times, the Lamp, the LCD Power C.B.A. or the
LCD Main C.B.A. may be defective.
Error Symptom Problem Possible Solutio

If the power supply outputs are good! Then I would say the back light inverter is bad! If the screen stays black and does not come on.

This sounds like micro glitch try unpluging the tv and all controlable inputs (PC, iLinks, or other such devices) wait 5 min then plug the tv only in and see if you have returned functions. if you should read the manuals of those devices to see if the control functions can be turned off.