Kyocera TASKalfa 420i, Service Manual

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2KR/2KS
1-4-55
1-4-4 Electric problems
Troubleshooting to each failure must be in the order of the numbered symptoms.
Problem Causes Check procedures/corrective measures
(1)
The machine does
not operate when the
main power switch is
turned on. 1. The power cord is not
plugged in properly.
Check the contact between the power plug and the outlet.
2. No electricity at the
power outlet.
Measure the input voltage.
3. Broken power cord. Check for continuity. If none, replace the cord.
4. Defective main power
switch.
Check for continuity across the contacts. If none, replace the main
power switch.
5. Defective power source
PWB.
With AC present, check for 24 V DC at YC1-1 on the power
source PWB, 5 V DC at YC1-6 and 3.3 V DC at YC1-5. If none,
replace the power source PWB.
(2)
The eject motor does
not operate. 1. Poor contact in the con-
nector terminals.
Reinsert the connector. Also check for continuity within the con-
nector cable. If none, remedy or replace the cable.
2. Defective drive transmis-
sion system.
Check if the rollers and gears rotate smoothly. If not, grease the
bushings and gears. Check for broken gears and replace if any.
3. Defective eject motor. Run maintenance item U030 and check if the eject motor oper-
ates. If not, replace the eject motor.
4. Defective engine PWB. Run maintenance item U030 and check if the eject motor oper-
ates. If not, replace the engine PWB.
(3)
The scanner motor
does not operate. 1. Poor contact in the con-
nector terminals.
Reinsert the connector. Also check for continuity within the con-
nector cable. If none, remedy or replace the cable.
2. Broken motor coil. Check for continuity across the coil. If none, replace the motor.
(4)
Power source fan
motor 1/2 does not
operate. 1. Poor contact in the con-
nector terminals.
Reinsert the connector. Also check for continuity within the con-
nector cable. If none, remedy or replace the cable.
2. Broken motor coil. Check for continuity across the coil. If none, replace the motor.
3. Defective motor. Run maintenance item U037 and check if the motor operates
when the following terminals on the PWB goes low. If not, replace
the corresponding motor.
Power source fan motor 1/2: YC4-1 on the power source PWB
4. Defective power source
PWB.
Run maintenance item U037 and check if following terminals on
the PWB goes low. If not, replace the power source PWB.
Power source fan motor 1/2: YC4-1 on the power source PWB