Saturday, February 21, 2015

JVC LT-32P679 -S, LT-32P679 - V SERVICE MODE AND POWER SUPPLY CIRCUIT

JVC LT-32P679/S, LT-32P679/V

 LCD TV 


SERVICE MODE AND POWER SUPPLY CIRCUIT 

SERVICE MODE
HOW TO ENTER THE SERVICE MODE
(1) Set to "OFF" using the [SLEEP] key.
(2) While "OFF" is displayed, press the [V. STATUS] key and [DISPLAY] key simultaneously.
(3) Enter the SERVICE MODE
(4) Select the 2.White balance base from the SERVICE MODE.
HOW TO EXIT THE SERVICE MODE
Press the [MENU] key to exit the SERVICE MODE
SELF CHECK FUNCTIONS
OUTLINE
This model has a self check function given below. When an abnormality has been detected, the power is turned off and the POWER LED flashes to inform of the failure. An abnormality is detected by the signal input state of the control line connected to the microcomputer.
Detection item
Detection content
Diagnosis signal (line)
Detection timing
Low bias line
short protection
Confirm the operation of the low bias (3.3V/5V/
12V/24V) protection circuit.
3.3V: Q7004 [SIGNAL PWB]
5V: Q7003 [SIGNAL PWB]
12V: Q7001 [SIGNAL PWB]
24V: IC7019 [SIGNAL PWB]
LB_PRO
At 10 seconds after the power is turned on, the
self-check function starts. If NG is detected during
3000ms, the power is turned off automatically.

METHOD OF DISPLAY WHEN A RASTER IS NOT OUTPUT
In the state where a raster is not output by breakdown of the set, an error is displayed by blink of the POWER LED.
Low bias line short protection ------------------LED turning on and off at 2 seconds intervals.

If an error is detected, the power is turned off. Shortly after the power is turned off, the POWER LED will be blinked. Power cannot be turned on until the power cord takes out and inserts, after the power is turned off.
POWER SUPPLY CIRCUIT 
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