Commodore 1526 Service Manual page 24

TROUBLESHOOTING GUIDE (Continued)
SYMPTOM 5: Improper Ribbon Feed
POSSIBLE CAUSE
SOLUTIONS
1. Obstruction of ribbon path. Check FPC cables for proper location.
Check ribbon guide for foreign matter.
2.
Defective ribbon cartridge. Check for proper ribbon insertion.
Check the rotation of the cartridge by manually
rotating the ribbon in the direction of the arrow.
3.
Defective mechanics. Check the ribbon drive gears for proper lubrication
(see page 5) and smooth opertion.
SYMPTOM 6: Carriage does not move correctly.
POSSIBLE CAUSE
SOLUTIONS
1. Physical obstruction in the Check that dirt or foreign objects have not
path of the head carriage. accumulated within the mechanism.
2. Carriage motor is defective. With power off, check the motor with an ohm-
meter. Place one of the leads on pin 13 of
J
1 and
read the resistance to pins 21, 22, 23 and 24 of
J 1 . A good carriage motor will read about 50
ohms.
Check for good mechanical and electrical connec-
tions to the motor and its wiring - see wiring
diagram on page 28.
Check for
+
26 VDC supply to the motor.
3. Circuit failure on PCB. Check motor circuitry on PCB. See circuit theory
on page 12 for proper circuit operation.
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