Sharp XV-Z2000 Service Manual page 36

XV-Z2000
DT-400
Checking the peripheral circuits of the
microprocessor
Are the voltages of approx. 3.3V and 2.5V
applied to both ends of C8001 and C8056
respectively?
YES
Are the oscillations of 133MHz and
74.25MHz outputted from pin (3) of
X8003 and pin (3) of X8007 respectively?
YES
Does each terminal of R8038, R8039,
R8041, R8042 and R8050 change?
YES
Do pins (15) and (16) of IC2002 change?
YES
Do pins (46) to (49) and (4) to (7) of
IC2002 change when any key is
operated?
YES
When the power button is pressed, does
the voltage of pin (7) of IC8006 become
3.3V?
YES
Do pulse-shaped waveforms appear at
pins (1), (2), (5) and (6) of IC8006?
YES
Does the voltage of pins (3) and (6) of
IC8003 change?
YES
Is the voltage of pin (2) of Q8002 5V?
YES
Does the fan rotate?
YES
Go to "Checking the lamp light-up".
NO
Go to "Checking the power supply
system".
NO
Check X8001, X8003 and their peripheral
circuits.
NO
Check IC8202 or IC8001 is defective.
NO
Check IC8203 or IC2002 is defective. The
I2C bus does not function normally.
NO
IC2002 is defective. The keys do not
function normally.
NO
IC8001 is defective.
NO
IC8006 is defective.
NO
IC8003 is defective.
NO
Q8002 is defective.
NO Check the power supply circuit or fan
circuit on the main circuit.
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