Troubleshooting - JVC AV-56WP74 Service Manual

AV-48WP74
AV-56WP74
4.1 SELF CHECK FUNCTIONS
• This model has self-check functions that inform of the failure of the TV by detecting abnormality.
• Operational state is always monitored and the identified is memorized on the record.
4.1.1 HOW TO ENTER THE SELF-CHECK MODE
(1) Set the <SLEEP TIMER 30MIN> with [SLEEP TIMER] key.
(Fig.1)
(2) During the <SLEEP TIMER 30MIN> display, press [DIS-
PLAY] key and [VIDEO STATUS] key at the same time.
(3) Then <TEST MODE> screen is displayed. (Fig.2)
(4) Press [ 4 ] key then <SELF-CHECK> screen is appear.
(Fig.3)
4.1.2 HOW TO EXIT FROM THE SELF-CHECK MODE
(1) By using the remote control unit, turn the power off. At this
time, the failure record is cleared.
(2) Take off the AC plug from the wall outlet. At this time, the
failure record is not cleared.
4.1.3 SELF-CHECK DISPLAY
The self-check results are shown on the following display.
Method of indication when the raster is not displayed (Fig.3).
Each failure is shown by turning POWER LED on and off at
specified intervals.
Item
X-ray protection
B1 over-current
protection
Low B short protection Turning on and off 2-second intervals
4.1.4 EXPLANATION FOR ACTIVATION OF SELF-CHECK
FUNCTIONS
• For X-ray protection, B1 over-current protection and low B
short protection, the power of the TV is turned off if NG is de-
tected.
Immediately after the power is turned off, POWER LED will be
turning on and off.
When the power is turned off, you cannot turn the power on
again until the AC plug is taken out and put in again.
• The latest failure is stored on the record at the end.
The failure record for each check item is counted to the num-
ber of 9 at the maximum, When more than 9 failures are stored
on the record, the counter remains stopped at 9.
• SYNC is neither counted nor stored in memory.
• Because of the timing of Vcc start-up and shut-down of the IC
connecting to the I2C bus during which the power is turned on
and off, the operation may be interpreted as an error.
In order to avoid the misinterpretation, the self-check functions
should be started at about 3 seconds after the power is turned
on.
1-64 (No.52105)

TROUBLESHOOTING

POWER LED ON / OFF intervals
Turning on and off 0.1-second intervals
Turning on and off 1-second intervals
SECTION 4
SLEEP TIMER
30MIN
TEST MODE
1. I
2. STATUS DISP.
4. SELF-CHK
5. CONVER OFF
ROM CORRECTION : ACT
ROM VERSION :
ITEM
XRAY
LOB
SYNC
MEM
VCD
AIO
TUN
PP
Fig.3 SELF-CHECK SCREEN
Fig.1
2 C STOP
Fig.2
RESULT COUNT
NG2 OCP NG2
OK TIM OK
M:OK S:OK HD:NG
OK AVSW OK
NG2 BS OK
OK YC OK
OK GCR OK
NG4 IP OK