Trouble Shooting - JVC PD-35DX Service Manual

4.1 SELF-DIAGNOSIS FEATURE
4.1.1 OUTLINE
This model has a "Self-diagnosis function," which checks the operation state of the circuits and informs us of a failure by flashing
POWER LED when a failure occurs.
Diagnosis is performed when power is turned on, and information input to the main microcomputer is monitored at all time.
Failure detection is based on input state of I
4.1.2 POINTS TO NOTE WHEN USING THE SELF-DIAGNOSIS FEATURE
POWER LED may flash to inform us of a failure in the following cases, in addition to when circuit failure occurs.
(1) Temporary defective transmissions across circuits due to pulse interruptions.
(2) Misalignment in the on/off timing of power for I
4.1.3 DETAILS
Self-diagnosis is performed for the following items
Detection
Type of error
part
Low bias D992
(2.5V / 3.3V / 5V / D993
9 V) line short D994
D995
D996
[MAIN PWB]
Abnormal rise of TH6671
temperature in [AUDIO PWB]
audio part of
Display unit
Abnormal power PDP
supply in PDP
(PANEL) (short-
circuit etc.)
Abnormal rise of TH101
internal [PDP POWER
temperature in PWB]
Display unit
Abnormal power IC506
supply voltage Q606
(5V/Vs/Vd) Q704
[PDP POWER
PWB]
Abnormal PDP
operation of PDP
(PANEL)
Abnormal rise of IC505
temperature in [PDP POWER
power supply part PWB]
of Display unit
SECTION 4

TROUBLE SHOOTING

2
C bus and the various control lines connected to the main microcomputer.
2
C bus (Vcc) when turning on/off the main power.
Receiver unit
Color of State of
LED POWER LED
RED Light RED
RED Flash every 1.0 RED
second
RED Flash every 1.0 GREEN
second
RED Flash every 1.0 GREEN
second
RED Flash every 1.0 GREEN
second
RED Flash every 1.0 GREEN
second
Display unit
Color of POWER LED
LED flash cycle
Flash1.0second Detection is performed every
/ Out1.0second
150ms.
If nine or more consecutive
errors are detected, the power
is turned off (and turns to
stand-by state).
Flash0.1second Detection is performed every 1
/ Out0.1second
second.
The power is turned off if the
temperature sensor operates
for 10 seconds or longer.
Flash0.1second Detection starts 5 seconds
/ Out1.0second
after the power is turned on.
Detection is performed every
16mS.
The power is turned off if NG
continues for 700mS.
Flash0.1second Detection starts 5 seconds
/ Out0.1second
after the power is turned on.
Detection is performed every
16mS.
The power is turned off if NG
continues for 300mS.
Flash1.0second Detection starts 5 seconds
/ Out1.0second
after the power is turned on.
Detection is performed every
16mS.
The power is turned off if NG
continues for 2000mS.
Flash2.0second Detection is performed every
s 0.5 second.
/ Out2.0seconds
If a temperature rises beyond
the temperature predetermined
for detection of error over the
predetermined
times the power is turned off.
Detection timing Unit
Receiver
Display
Display
Display
Display
Display
permissible
(No.52089)1-45
PD-35DX