Casio PZ-3100 Service Manual page 10

Repair Item 2-B
When the waveform at IRF with an
osilloscope.
Check IC103 pins 32, 34, 4, 5, 36,
37, 38, 57, 21 and circuit around
them.
Check IC103 pins 8, 9 and 77.
IC104 or IC103 is defective.
B
Is the waveform
at IC102 pin 35 like that
shown in fig. 7 ?
Yes
Check soldering of C159 and IC103 pins
No
35 and 21.
IC103 is defective.
8
~1.1 V
Figure 7