Brother MP-21C Service Manual page 106

(3) The carriage motor does not rotate.
Possible cause Step
Connection 1
failure of the
Carriage motor
harness P4
Carriage motor 2
Driver circuit
(4) CR error
Possible cause Step
Connection 2
failure of the
Encoder FPC
P6 harness P4
Encoder strip 1
Carriage motor 2
(5) No paper supplied from ACSF
Possible cause
ACSF attached
incorrectly
Pick-up roller
ASSY
Separation pad
Check
Is the Carriage motor harness
P4 securely connected on the
Main PCB?
Disconnect the Carriage motor
harness P4 from the Main PCB.
Measure the resistance between
the connector pins of the
carriage motor with a circuit
tester.
Does the measured resistance
satisfy the value in the table
below?
P4-1 and P4-2 Approx.12
Check
Is the Encoder FPC cable P6
securely connected to the Main
PCB?
Encoder strip is contaminated
with dust.
Encoder strip is contaminated
with oil or ink.
Check the Carriage motor
operation referring to (3) if the
carriage motor does not rotate.
Step Check
1 Is the ACSF attached correctly?
2 Rotate the gears with your finger.
Does the Pick-up roller ASSY
rotate?
3 Is there any damage on the
Separation pad?
IV-5
Result
NO Connect it securely.
NO Replace the Carriage
motor ASSY.
YES
Replace the Main
PCB.
[
Result
NO Connect it securely.
YES Blow the dust out with
an air brush.
YES Clean it with alcohol,
then reassemble it. If
the problem still
remains, replace it with
a new one.
Result
NO Attach it correctly.
NO Replace the Pick-
up roller ASSY.
Yes Replace the
Separation pad
ASSY.
Remedy
Remedy
Remedy