Brother XR9000 Service Manual page 151

Repair Manual
Problem Primary factors and causes
13 Cannot sew BH
• BH is blocked Bad BH switch lever connecting
• BH cannot point
switch
Bad BH lever
• BH switches
BH lever operation drags
part way
BH presser foot button
through
attachment holder is pulled out
fully
BH switch assy. and main PCB
assy. connector disconnected
Bad main PCB assy.
• Becomes Bad feed forward / reverse
straight line adjustment
14 Bobbin winder Bad rubber ring of bobbin winder
shaft not turning assy.
Bad BW switch assy. attachment
position
Bad BW switch assy.
Bad main PCB assy.
Bobbin winding Bad bobbin presser adjustment
amount unsuitable
Loose bobbin presser
attachment screw
Bobbin winder Bad bobbin winder guide assy.
winds unevenly height adjustment
Loose bobbin winder guide
assembly screw
15 Foot controller not Bad foot controller
effective
FC jack assy. and main PCB
assy. connector disconnected
Bad FC jack assy. contact point
Bad main PCB assy.
6 - 8
Repair method
Adjust BH switch lever position
(4-16)
Replace BH switch assy.
(2-32) (3-47)
Reset range for BH presser foot
button attachment (More back
two marks from maximum
permissible range) (4-16)
Plug connector in (3-13)
Replace main PCB assy.
(2-13) (3-13)
Adjust feed forward / backward
(4-14)
Replace rubber ring
(2-19) (3-5)
Reattach BW switch assy.
(2-19) (3-5)
Replace BW switch assy.
(2-19) (3-5)
Replace main PCB assy.
(2-13) (3-13)
Adjust bobbin presser position
(4-15)
Adjust bobbin winder guide
assy.(4-15)
Replace foot controller
Plug connector in (3-13)
Replace FC jack assy.
(2-15) (3-11)
Replace main PCB assy.
(2-13) (3-13)
Items for Inspection method
Inspection and standards
button hole Check that there is no
stitch skipping or
clogging with BH
pattern sewing.
With the BH presser
foot moved the extent
of its range by hand,
confirm that there is
slack on the BH side
and the other side.
Bobbin winder Operate the bobbin
function winder with Schappe
Spun Sewing Thread
#60, and confirm that
there is no uneven
bobbin winding or
abnormal noises.
Check that the amount
of thread wound onto
the bobbin is 80 - 90%
of the bobbin diameter.
Foot controller Run the sewing
function machine using the foot
controller, and check
that the sewing
machine speed
changes according to
the amount it is
pressed down.