Brother PC8200 SUPER GALAXIE 2000, Service Manual

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*

 You must turn off the power and remove connectors from printed circuit boards before measuring resistance.

PROBLEM

CHECK

REMEDY

1. When power is turned

on, buzzer does not
sound and nothing
appears on display.

1) Has the display contrast been adjusted?
2) If the voltage between both inlet terminals is

measured when the power cord is plugged in, is the
standard voltage (120 VAC, 220V, 230V, 240V)
displayed?

3) When power switch is set to on, is resistance between

both ends less than 1 

W

?

4) Remove connector CN13 from the power supply

board, and check following voltages using a tester:
Voltage between pins 4 and 5 should be 8 to 12 VDC.
Voltage between pins 6 and 7 should be 22 to 26 VDC.

5) Is fuse blown?

6) Others

1) Adjust the contrast.
2) Replace the power cord.

3) Replace power supply unit

assembly.

4) Replace power supply unit

assembly.

5) Replace fuse after correcting defect

that caused fuse to blow.

6) Replace SS PC board assembly.

2. After the power is

turned on, pulse motors
do not return to their
home positions with
respect to the needle
position. (Zigzag pulse
motor when needle bar
is raised and feed and
horizontal feed pulse
motors when needle
bar is lowered.)

1) Are the resistances between the connector pins given

below normal for the pulse motors which do not return
to the home position?
Zigzag

(CN13)...... 1-3, 2-3, 4-5, 4-6 

®

 8-10 

W

Feed

(CN16)...... 1-3, 2-3, 4-5, 4-6 

®

 8-10 

W

Horizontal (CN17)...... 1-6, 2-5, 3-6, 4-5 

®

 8-10 

W

2) Set the home position for the same pulse motors

irrespective of needle position.

3) Is a fuse blown?

4) Is the voltage between pins 4-5 normal when the

output connector (CN7) is disconnected from the main
power board ?
Between 4-5

22-26 VDC

5) Others

1) Replace the pulse motor which

shows an abnormality.

2) Replace NP board assembly.

3) Replace fuse after correcting defect

that caused fuse to blow.

4) Replace power supply unit

assembly.

5) Replace main PC board assembly.

3. Pattern cannot be

selected.

1) Does switch on SS (VR) PC board remain pressed?

2) When the foot controller is connected, does it remain

depressed?

3) Others

1) Adjust or exchange SS (VR) PC

board assembly.

2) Check foot control unit operation.

3) Replace LCD module.

4. Main motor does not

run.

1) Does balance wheel rotate easily?
2) Is main motor connector (CN2 on power supply unit)

attached properly?

3) Is resistance of both ends on main motor connector

(CN2 on power supply unit) 24 to 34 

W

?

4) Do start/stop switch, needle position switch, and

thread cutter switch operate correctly?

Voltage between ends of each switch should be;
under 1 

W

 when switch is pressed.

infinite when switch is released.

5) Is presser foot lifter lowered? Does presser foot switch

operate correctly?

When presser foot lifter is raised, voltage between
pins 2-1 of fabric thickness detector (CN14) is
approx. 1.5 VDC.
When presser foot lifter is lowered, it is approx. 4
VDC.

6) Others

1) Adjust balance wheel position.
2) Check connector connection.

3) Replace main motor.

4) Replace SS PC board assembly.

5) Check fabric thickness detection or

replace fabric thickness sensor
assembly.

6) Replace main PC board or power

supply unit assembly.