Troubleshooting - JVC LT-Z37DX5 Service Manual

5.1 SELF CHECK FEATURE
5.1.1 OUTLINE
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 I
the various control lines connected to the main microcomputer.
5.1.2 HOW TO ENTER THE SELF CHECK MODE
Before entering the SERVICE MODE, confirm that the setting of
VCR/TV/ DVD switch is at the "TV" side. If the switches have not
been properly set, you cannot enter the SERVICE MODE.
(1) Press the [DISPLAY]
simultaneously, then enter the SERVICE MODE.
(2) Press the [2] key SELF CHECK MODE.
(3) Press the [ZOOM] key to enter Page 2 of the SELF CHECK
MODE.
*Use the [CINEMA] key to toggle between Page 1 and
Page 2.
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.
5.1.3 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.
5.1.4 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.
1-24 (No.YA362)
SECTION 5

TROUBLESHOOTING

2
C bus and
key and [MUTING] key
5.1.5 POINTS TO NOTE WHEN USING THE SELF CHECK
FEATURE
In addition to circuit failures (abnormal operation), the following
cases may also be iagnosed as "Abnormal" and displayed and
counted as "NG".
(1) Temporary defective transmissions across circuits due to
pulse interruptions
(2) Misalignment in the on/off timing of power for I
(VCC) when turning on/off the main power.
Diagnosis may be impeded if a large number of items are
displayed as "NG". As such, start Self check check only after 3
seconds in the case of receivers and 5 seconds in the case of
panels upon turning on the power. If recurrences are expected,
ensure to clear (reset) the failure history and record the new
diagnosis reults.
SERVICE MODE SCREEN
SERVICE MENU SERVICE MENU
1.ADJUST 1.ADJUST
2.SELF_CHECK 2.SELF_CHECK
3.I2C STOP 3.I2C STOP
SELF CHECK MODE SCREEN (Page 1)
LOB LOB OK OK FAN FAN
SYNC M:OK S:OK HD:NG SYNC M:OK S:OK HD:NG
TIM TIM OK OK
MSM MSM OK OK DIGI 0000 DIGI 0000
MEM MEM OK OK AVSW OK AVSW OK
YC YC OK OK AIO AIO
TUN TUN OK OK GCR GCR
IP IP OK OK RGB RGB
DVI DVI OK OK HDMI OK HDMI OK
Item
SELF CHECK MODE SCREEN (Page 2)
FAN FAN OK OK ALM ALM
TMP TMP OK OK
ATP ATP OK OK ASH ASH
PNL PNL OK OK MEM MEM
TMP TMP OK OK AIO AIO
Item
* As "SYNC" is not counted, the number of failures not displayed.
2
OK OK
OK OK
NG 1 NG 1
OK 8 OK 8
CHECK
Normality=OK
Abnormality=NG
OK OK
OK OK
OK OK
OK OK
CHECK
Normality=OK
Abnormality=NG
Fig.1
C bus