JVC AV-14F1P(PH), Service Manual

Page: 25 / 27

AV-14F1P
No. 56084 25
SELF-CHECK FUNCTIONS
1. Outline
This model has self-check functions given below. When an abnormality has been detected, the SUB POWER is turned off and the ON
TIMER LED flashes to inform of the failure. An abnormality is detected by the signal input state of the control line connected to the
microcomputer.
2. Self-check items
[ Indication by the LED ]
Item LED flashing intervals Priority of detection
Over-current protection/X-ray protection At 0.5-second intervals 1
CRT NECK protection At 1-second intervals 2
Check item
Over-current protection
CRT NECK protection
X-ray protection
Details of detection
An over-current on the low B line
is detected.
Also, an over-current for speaker
drive is detected.
Operation of CRT NECK protec-
tion circuit
Operation of X-ray protection cir-
cuit.
Method of detection
The microcomputer detects the
possible abnormality at 1-sec.
intervals.
If NG state is detected for more
than 1 ms, the microcomputer
judges that there is an abnormal-
ity.
DITTO
DITTO
State of abnormality
When an abnormality has been
detected, the SUB-POWER is
turned off. While the SUB-
POWER is being turned off, the
POWER key on the remote con-
trol unit is not operational until the
power cord is taken out and put
in again.
DITTO
DITTO
3. Self-check indicating function
When an abnormality has been detected at about 5 seconds
after the power is turned on, the SUB POWER is turned off
immediately and the ON TIMER LED flashes.
After about
5 seconds
Power on
Start of
detection
Detection of
an abnormality
SUB-POWER OFF
Flashing ON TIMER LED