Brother MD-602 Service Manual page 38

Control PCB
When power is ON, an error
sign FU appears.
Something is wrong with
the operation of sewing
head and motor.
Power transformer
When power SW is ON, LED
(Red) does not illuminate.
32
8A fuse blown?
8A fuse OK?
Fuse F101, F102 blown?
MD-602, 612
Check transistor for solenoid
Check power transformer
Check resistance value at the
primary side of transformer.
Is there about 15ohm?
Check BD101.
Replace fuse
Replace control PCB
Replace transformer
Replace BD101