Toshiba CN27E90 Technical Training Manual page 132

(A) OSD AND PICTURE DO NOT APPEAR
Check that heater or CRT lights.
OK
Power supply of CRT Drive board.
9V, 200V
OK
Check waveform of TP-47R, G, B.
OK
Check waveform of TP-46R, G, B.
OK
Check Q501 power.
Pins 22, 40, 46---------- 9V
Pin 12---------------------- 5V
OK
Check waveform of I 2 C bus line.
OK
Check Q501 and peripherals.
NG
Check R920 (heater resistor) and
power/def circuit.
NG
Check power/def circuit.
NG
Check CRT and power/def
circuit.
NG
Check Q907, Q910 and blanking
circuit. (pow/def board)
NG
Check power line and power/
def circuit.
NG
Check I 2 C bus line and
QA01 (MICOM).
Check QA01 and periheral circuit.
132