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CONDITION
PROBLEM SYMPTOMS
COUNTERMEASURES
6. Embroidery
frame operation
is not normal.
1) Is the rotary shutter correctly positioned?
2) Is the resistance between the following
pulse motor connector pins normal?
X (CN16).. Between 1-2, 3-4
→
Approx. 3
Ω
Y (CN17).. Between 1-2, 3-4
→
Approx. 4
Ω
3) When the hand wheel is rotated slowly in
reverse, does the voltage between 2-5, 3-
5 and 4-5 in the NP PC board assembly
connector (CN10) fluctuate between 0 to
5 V DC?
4) Other
1) Adjust (see page 16.)
2) Replace the defective pulse motor.
3) Replace the NP PC board assembly.
4) Replace the main PC board assembly.
7. LCD does not
operate
normally.
1) Is the voltage between 8-7 in the LCD
module connector (CN5) -5 to -10 V DC?
2) Other
1) Replace the main PC board assembly.
2) Replace the LCD module assembly or
the main PC board assembly.
8. LCD backlight
does not work.
1) Disconnect the output connector (CN1)
from the power supply PC board; is the
voltage between 3-4 normal?
Between 3-4 .......................13 to 18 V DC
2) Is the voltage between 9-10 of the LCD
module connector (CN5) 9V DC?
3) Other
1) Replace the power supply unit assembly.
2) Replace the main PC board assembly.
3) Replace the LCD module assembly.
9. Bobbin winding
is not possible.
1) Is the resistance between both sides of
the bobbin winder switch connector (CN4)
less than 1
Ω
during bobbin winding and
∞
(infinite) at all other times?
2) Is the installation correct?
3) Other
1) Replace the bobbin winder switch
assembly.
2) Adjust (see page 21).
3) Replace the main PC board assembly.
10.Needle thread
detection does
not operate
normally.
1) Is the voltage between 2-3 to the needle
thread breakage sensor connector (CN9)
normal when the thread is tensioned and
released with the needle thread correctly
threaded in the thread path?
When thread is tensioned ............... 0 V
Ω
When thread is released ................. 5 V
Ω
2) Other
1) Adjust the thread take-up spring; if the
problem remains, replace the thread
breakage sensor PC board assembly
(see p.20).
2) Replace the main PC board assembly.
