Sharp UX-B20 Service Manual page 41

5. Overall troubleshooting of Printer
• BOTH CARRIER MOTOR AND FEED MOTOR
ARE NG.
FUSE "FU101"
OK
+30V CNHEAD1(8PIN)
OK
CHECK IC10
OK
REPLACE CONTROL PWB
• FEED MOTOR IS NG (CARRIER MOTOR IS
GOOD)
CHECK WAVEFORMS IC10 (19,21,25,27PIN)
REPLACE FEED MOTOR
• CARRIER MOTOR IS NG (FEED MOTOR IS
GOOD)
CHECK WAVEFORMS IC10 (19,21,25,20PIN)
REPLACE CARRIER
REPLACE FU101
OPEN
CHECK RESISTANCE
BETWEEN +30V AND GND.
NG
SHORT OR NOT
SHORT
REPLACE CONTROL PWB
REPLACE IC10
NG
OK
OK
CHECK +30V PATTERN
NO
REPLACE CONTROL PWB
NG
REPLACE CONTROL PWB
NG
3 – 4
UX-B20U/UX-B20C/B25C