JVC C-N14210/S Service Manual page 23

SELF CHECK FUNCTIONS
1. Outline
This model has self check functions given below. When a malfunction has been detected, the POWER is turned off and the LED flashes to
inform of the failure. The malfunction is detected by the signal input state of the control line connected to the microcomputer.
2. Self check items
Check item
CRT NECK protector
Also detected if the
power supply line output
from the HVT (High
voltage Transformer) has
shorted with the ground.
3. Self check indicating function
The self-check function begins detection about 5 seconds after
power is supplied.
In the event a malfunction is detected, the power is cut off
immediately.
At this time, the ON-TIMER LED flashes to inform of the
malfunction.
[ON-TIMER LED indication]
The ON-TIMER LED flashes at 0.5 seconds intervals.
Details of detection
When the vertical circuit S- The microcomputer detects at 1-
correction capacitor C427 second intervals.
is shorted, detect the
If NG is detected for more than 1
potential drop of the C427,
ms, a malfunction is interpreted.
and prevent the burn
damage to the CRT NECK.
(Grounding of shorting of
the power supply output
from the HVT to the vertical
circuit, and the small signal
power supply is also
detected.)
No. 51831
Method of detection
POWER After about
Supplied 5 seconds
Start of
detection
C-N14210
State of malfunction
When a malfunction has been
detected, the POWER is turned
off. While the POWER is being
turned off, the power key of the
remote controller is not operational
until the power code is taken out
and put in again.
Malfunction
is detected
POWER OFF
Flashing
ON-TIMER LED
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