Epson MX-80 Technical Manual page 57

*C
•f
SYMPTOM 6
Paper feeding Is not performed at all or the paper feeding motor vibrates and Is not operating
properly.
No. Cause of Trouble
Defective paper feeding
motor assy or driver circuit
board
LF B
(Q15)
LF D
(Q17)
Check Point
• If PIS sensor board is not defective in
the above check, check the four line
feed driving transistors (Q14—Q17) for
normal collector waveform output (at
Pin Nos. 25-28 of CN6).
124V
Approx. 8.4 ms
LF C
(Q16)
3-19
Repair Method
• If the collector wave form is
normal (proper voltage is out
put for each phase), the paper
feeding motor is defective.
Replace it with a new one. See
paragraph 3.3.3 (6) for re
placement.
• If the collector waveform is
abnormal (proper voltage is
not output for each phase), the
driver circuit board is defec
tive. Replace it with a new one.
See paragraph 3.3.2 (1) for
replacement.
REV. A