Epson Stylus COLOR 300 Service Manual page 34

EPSON Stylus Color 300 Service Manual
Symptom Condition
Self-test No printing.
printing is
abnormal.
Carriage Drive signals
does not are not
operate output
normally. correctly.
5-2
Cause
PWM signal is Is PWM signal waveform correct at pin
not output. 140 of IC1?
Head drive Check waveform of the signal VO:
voltage
generation
circuit does
not operate.
CPU (IC2) is Is the signal waveform correct at pin 5/6
defective of IC2?
CR Motor Is the signal waveform correct at pin
driver (IC8) is 3/6/18/21 of IC8?
defective
Checkpoint Solution
Replace IC1
Replace any
defective
components:
Q1/2/4/7/8 or
QM1/3/4/5/6/7/8
Replace IC2
Correct:
Replace CR
Motor
Incorrect:
Replace IC9
Rev. A