Toshiba 21A3E Service Manual page 8

8. SELF DIAGNOSTIC FUNCTION
1) Press "9" button on Remote Control during display of adjustment menu in the service mode.
The diagnosis will begin to check if interface among IC's are executed properly.
2) During diagnosis, the following displays are shown.
<SELF CHECK>
23******
POWER : 00
BUS LINE : OK
BUS CONT : OK
BLOCK : UV V1 V2
Part number of microcomputer (QA01)
Operation number of protecting circuit ----"00" is nor-
mal.
When indication is other than "00", overcurrent apts to
flow, and circuit parts may possibly be damaged.
BUS LINE CHECK ----"OK" is normal.
"SDA1-GND" ------------- SDA-GND short circuit.
"SCL1-GND" -------------- SCL-GND short circuit.
"SCL1-SDA1" ------------- SCL-SDA short circuit.
BUS CONT ----"OK" is normal.
When indication shows "Q uuu NG", the device with
the number may possibly be damaged.
BLOCK
UV : TV reception mode
V1 : VIDEO 1 input mode (a1)
V2 : VIDEO 2 input mode (a2)
The items marked with
*
QV01
are not usable to display in the SELF DIAGNOSTIC FUNCTION for some model.
Indicated color of mode now selected : Green and Red
Indicated color of other modes
Green : Normal
Red : The microcomputer operates to provide judgement
of no video signal. The red color is still indicated
though the signal is input, failure may exist in input
signal line including QV01.
QV01 : In case of indication green ---Normal
In case of indication red with input signal----
Failure may exist in output line including QV01.
NOTE: Component which controls character display on
screen is QT01 (TELETEXT IC.). If this display
function fails to operate due to damage in QT01,
self diagnosis procedure is as follows.
(1) In case that power indicator is blinking with
interval of 0.5 seconds; it means protecting
circuit (Current limiter) is operating, and cir-
cuit components may possibly be damaged.
Check related components.
(2) In case that power indicator is blinking with
interval of 1 second; Protecting circuit does
not operate, but a part of Bus line does not
operate normally. Check Bus line.
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: White