Brother DB2-DD7100A Instruction Manual page 166

15. TROUBLESHOOTING
Problem
19. "L" flashes in LED display
shortly after power is turned on
and treadle is pressed.
20. Machine does not operate
when power is turned on and
treadle is pressed.
(1) Operating panel power
indicator does not illumi-
nate.
(2) O n l y o p e r a t i n g p a n e l
power indicator illumi-
nates.
21. Machine does not operate at
high speed.
22. Machine stops during sew-
ing.
23. Bobbin thread detector does
not operate.
147
● Is the motor connector inside
the control box disconnected?
Insert the connector securely.
● Has the machine locked up?
Turn off the power and then
turn the machine pulley by
hand and check that it turns
easily.
● Is the power supply connector
disconnected from the control
box?
Insert the connector securely.
● Is the power supply plug incor-
rectly wired or is the voltage
incorrect?
Check the power plug wiring
and the power supply voltage.
(Try inserting into a different
wall socket.)
● Is DIP switch No. 8 inside the
control box set to ON?
Set DIP switch No. 8 to OFF.
● Is the sewing speed setting or backtack speed setting incorrect?
Set the speed to a higher speed using the operating panel.
● Is the power supply voltage too low?
Check the power supply.
(If the power cord is too long or too many appliances are being run
from a single outlet, this may cause voltage drops which will in
turn cause the reset function to activate and stop the machine, even
if the power supply itself is normal.)
● Is the bobbin thread detector con-
nector inside the control box discon-
nected?
Insert the connector securely.
DB2-DD7100A
Possible cause Page
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