Sharp MD-C2 Service Manual page 76

MD-C2
• Disc motor fails to run
Does waveform appear on the pins 24 and 25 of IC1201 in the
TEST mode focus gain coarse adjustment step?
Does waveform appear on the pins 9 and 10 of IC1601, pins 7
and 8 of CN1401 ?
Replace the completed disc motor.
• Tracking servo failure
Does waveform appear on the pins 34 and 35 of IC1601, and
pins 2 and 4 of CN1101, and pins 1 and 3 of CN1910 in the TEST
mode focus gain adjustment step?
Replace the optical pickup.
• Slide servo failure
Does the pickup move to external and internal periphery when
the or button is pressed in the TEST mode?
Is there any change on the pins 22 and 23 of IC1201 when the
or button is pressed?
Is there any change on the pins 14 and 15 of IC1601, and the
pins 11 and 12 of CN1401 when the
pressed?
Does voltage on the positive and negative terminals of slide
motor change when the or
Replace the slide motor.
Yes
Yes
Yes
No
Yes
or button is
Yes
button is pressed?
Yes
Check soldering joint and parts of pins 24 and 25 of IC1201, and
No
peripheral circuit.
Check soldering joint of IC1601.
No
Check the soldering joint of pins 20 and 21 of IC1201, CN1101 and
No
IC1601.
Check the waveform on the pins 22 and 23 of IC1201, check the
Yes
peripheral parts and soldering joint.
Check the waveform on the pins 22 and 23 of IC1201, check the
No
peripheral parts and soldering joint.
Check the soldering joint of IC1601, and CN1401
No
Check the soldered selections of CN1401, CN1921 and CN1901.
No
Check the soldered section connected to the sled motor.
Check to see if the trace is broken.
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