Brother LK3-B430E Mark II Service Manual page 97

Error status Probable causes
#17 3. Main circuit board defective
Thread
take-up
lever does
not
operate.
#18
1. Poor adjustment
The
machine
does not
stop with
the needle
at the
upper
2. Synchronizer defective
position
after
thread
trimming
3. Cable defective
(Error
code E-50
appears
on the
4. Power supply circuit board
display
defective
window).
Main circuit board
5. Main circuit board defective
6. Motor defective
With connector P4 (SOL2) on the main circuit
board removed, turn on the power, perform
sewing, and measure the voltage across pins
1 and 2 of connector P4.
If there is a sudden voltage output at the end
of sewing, it is OK.
Thread trimmer
a. See 6-17. "Adjusting the needle up stop
b. If the pulley turns after the machine stops,
See #14-1.
See #13-1.
With P13 (DC18) connectors plugged in on the
main circuit board, measure the voltage in the
connector on the cable.
If the voltage across the following pairs of
pins, pins 1 and 2, pins 4 and 5, and pins
10and 11 is DC 15 - 18 V, it is OK.
LK3-B430E Mark II
Check/repair/adjust
position," and 6-18. "Adjusting the V-belt
tension" for adjustment.
this is not an electrical problem.
10. ELECTRIC MECHANISM
Parts to be replaced
V-belt
Power supply
circuit board
Main circuit board
Motor
90