JVC LT-32BX SERIES LCD TVs _ SELF CHECK MODE_ DETAILS
SELF CHECK FEATURE
This unit comes with the "Self
check" feature, which checks the operational state of the circuit and
displays/saves it during failure.Diagnosis is performed when power is turned
on, and information input to the main microcomputer is monitored at all time.Diagnosis
is displayed in 2 ways via screen display and LED flashes. Failure detection is
based on input state of I2C bus and the various control lines
connected to the main microcomputer.
TO ENTER SELF CHECK MODE
- Press the [RETURN+] key and [MUTING] key simultaneously, then enter the SERVICE MODE.
- Press the [2] key then enter the SELF CHECK MODE.
NOTE:
When a number key other than the [2] key is pressed in the SERVICE MODE
screen, the other relevant screen may be displayed. This is not used in the SELF CHECK MODE. Press the [MENU] key to return to the MAIN MENU SCREEN.
TO EXIT SELF CHECK MODE
- Turn off the power by unplugging the AC power cord plug when in the Self check display mode.
TO CLEAR [RESET] FAILURE HISTORY
- Turn off the power by pressing the [POWER] key on the remote control unit when in the Self check display mode.
FAILURE HISTORY
- Failure history can be counted up to 9 times for each item. When the number exceeds 9, display will remain as 9. Failure history will be stored in the memory unless it has been deleted.
NOTE:
Only
SYNC (with/without sync signals) will be neither counted nor stored.
POINTS TO NOTE WHEN USING THE SELF CHECK FEATURE
In addition to circuit failures
(abnormal operation), the following cases may also be diagnosed as
"Abnormal" and counted.
- Temporary defective transmissions across circuits due to pulse interruptions.
- Misalignment in the on/off timing of power for I2C bus (Vcc) when turning on/off the main power.
Therefore, turn on the main power, and then wait
for about 3 seconds before starting Self check. If recurrences are expected, ensure to clear (reset) the failure history
and record the new diagnosis results
SELF CHECK MODE DETAILS
Detection
item
|
Display
|
Detectection
content.
|
Diagnisis
signal [line]
|
Detection
timing
|
Low bias line short
protection
|
LOB
|
Confirm the operation of the low
bais(5V/14V/16V/24V)
protection circuit.
5V: Q9201, Q9301 [DIGITAL PWB]
14V: Q9503 [POWER PWB]
16V: Q9505 [POWER PWB]
24V: Q9506 [POWER PWB]
|
PROTECTOR
|
Detection starts 3 seconds after
the power is turned on. If error continues between 200ms the
power is turned off.
|
MAIN MEMORY
|
MEM
|
Confirmation of reply
of ACK signal which uses I2C
communication.
IC7002 [DIGITAL PWB]
|
SDA
|
Detection starts 3 seconds after
the power is turned on.If it checks
whenever I2C communication is performed and no reply of ACK signal an error will be counted.
|
AUDIO
|
AIO
|
Confirmation of reply of ACK signal
which uses I2C
communication.
IC6002 [DIGITAL PWB]
|
SDA
|
Detection starts 3 seconds after
the power is turned on.If it checks
whenever I2C communication is performed and no reply of ACK signal an error will be counted
|
RF TUNER
|
TUN
|
Confirmation of reply of ACK signal
which uses I2C
communication.
TU1001 [ANALOG PWB]
|
SDA
|
Detection starts 3 seconds after
the power is turned on.If it checks
whenever I2C communication is performed and no reply of ACK signal an error will be counted
|
HDMI
|
HDM
|
Confirmation of reply of ACK signal
which uses I2C
communication.
IC8502 [DIGITAL PWB]
|
SDA
|
Detection starts 3 seconds after
the power is turned on.If it checks
whenever I2C communication is performed and no reply of ACK signal an error will be counted
|
SYNC SIGNAL
|
SYN
|
Confirmation of presence of sync
signal in selected
video signal.
IC7001 [DIGITAL PWB]
|
===
===
|
The selected video input signal is always checked and if there is the
sync signal, it is displayed as
"OK", and if not as
"NG".
|
In the state
where a raster is not output by breakdown of the set, an error is displayed by
blink of the POWER LED.
- Type of error: Low bias line short protection.
- POWER LED flash cycle: Power LED turnig on and off at 1 second intervals
Explanation
of operation
If error is detected, the power is
turned off. Shortly after the power is turned off, POWER LED will be blinked.
When the protection of low bias line
short operates, the power cannot be turned on until the power cord takes out
and inserts, after the power is turned off.
