JVC LT-37X688 Service Manual page 32

5.1.4 HOW TO EXIT THE SELF CHECK MODE
TO SAVE FAILURE HISTORY:
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.
5.1.5 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.
5.1.7 DETAILS
Self check is performed for the following items:
<SELF CHECK MODE(TV-MICRO)>
Detection item
Low bias line short LOB
protection
Fan lock FAN
Audio AUD
Devices on the ANALOG ANA
PWB
Devices on the DIGITAL DIG
PWB
<SELF CHECK MODE(DIGITAL)>
Detection item
MTS decoder BTSC Dec Confirmation of reply of ACK signal which uses
A-D converter for compo- Comp.ADC Confirmation of reply of ACK signal which uses
nent video
1-32 (No.YA535)
Display Detection content
Confirm the operation of the low bais (5V / 12V / 14V
/ 24V) protection circuit.
IC9651, Q9051, Q9151[ANALOG PWB]
Not used
Not used
Confirmation of reply of ACK signal which uses
2
I C communication.
IC6601 [ANALOG PWB]
Confirmation of reply of ACK signal which uses
2
I C communication. [DIGITAL PWB]
Display Detection content
2
I C communication.
IC2101 [DIGITAL PWB]
2
I C communication.
IC2201 [DIGITAL PWB]
5.1.6 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.
(1) Temporary defective transmissions across circuits due to
pulse interruptions.
(2) Misalignment in the on/off timing of power for I
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.
Diagnosis
signal (line)
LB_PRO
----
----
SDA
SDA
Diagnosis
signal (line)
SDA
SDA
2
C bus (Vcc)
Detection timing
At 3 seconds after the power
is turned on, the self-check
function starts. If NG is
detected during 200ms, the
power is turned off
automatically.
----
----
Detection starts 3 seconds
after the power is turned on. If
2
it checks whenever I C
communication is performed
and no reply of ACK signal an
error will be counted.
Same as above.
Detection timing
2
If it checks whenever I
communication is performed
and no reply of ACK signal an
error will be counted.
Same as above.
C