Sharp CD-C500Z, Service Manual, Page: 20 / 56

Is the laser control signal of pin 38 (LANF) of the
microcomputer
at a low level?
Is the Q7 laser diode driver
No
emitter voltage
Yes
Replace the optical pickup.
Is the pickup returned to the innermost part?
Is the pickup in switch SW1 turned to ON?
Yes
Check if pins 57 (FEM+) and 58 (FEM-) of ICI are
outputting.
Defective
l
is defective. Replace it.
Normal
Check pin 8 of the slide motor driver (IC5).
Normal
The slide motor driver(lC5) is defective.Repace it.
Check if there is voltage at and Ml.
Is there audio output?
No
Is there audio output from both L channels?
Yes
l
Check the muting Transistor, Q6 and Q8 and replace.
No
l
Check the sound coupling capacitors
Is there 5V at
Yes
Check power circuits and
N o
Is pin 36 of muting output at a high level?
Replace
No
Is pin 3 of Q6 and Q8 at a low level?
No
Check the voltage of and and replace faulty
parts.
Yes