Failure Investigation
for Electronic Parts
4 - 2
Failure Investigation fo
r Ele
ctro
ni
c Pa
rts
Failure Investigation fo
r Ele
ctro
ni
c Pa
rts
Sewing lamp does not light
Sewing lamp does not light.
Replace the motor 3P supply assy.
N
Replace the foot controller.
Y
Replace the LED lamp assy.
When unplug the foot controller plug
from the socket of the machine, is the
voltage between pins A of the plug 108
to 132V AC? (for 120V AC countries) *
1
Y
N
N
Connect it properly.
Is the LED lamp assy connector
connecte d to the power supply
PCB (CN2) correctly?
Y
* Refer to Fig.
1
.
* Refer to Fig.
2
.
Fig.
2
When disconnect the LED lamp assy
connector from the power supply PCB
(CN2), is the voltage between pins 1
and 2 at CN2 10 to 12V DC?
* Refer to Fig.
2
.
CN2
1
2
LED lamp lead wire
Power supply PCB
*1 For 220 to 240V AC countries : 198 to 264V AC
Fig.
1
A
