Brother LZ2-B855E Service Manual page 92

8. ELECTRIC COMPONENTS
Error Probable causes
status
# 14. 1. Power turned on when treadle
EE6
was depressed forward or
backward
2. Malfunction of adjusting
treadle
3. Malfunction of harness
1. Power turned on while panel
# 15.
EE7,
key was being pressed
EE8
2. Malfunction of panel
1. Malfunction of synchronizer
# 16.
EE9
2. Incorrect machine motor
pulley diameter
3. DIPSW1-2 is turned ON
1. Abnormal rise in power supply
# 18.
EF2
voltage
2. Upper shaft is locked
1. Poor connection of P-ROM
# 19.
EF3,
EF4,
2. Problem of P-ROM data
EF5
1. Malfunction of panel circuit
# 20.
LED does board
not flush 2. Panel key is locked
when SET
key is
pressed
# 21. 1. Max. sewing speed is limited
Sewing 2. Treadle is not adjusted
machine correctly
3. Malfunction of harness
does not
operate
correctly in 4. Malfunction of treadle unit
accordance
with the
treadle
depression
amount.
# 22. 1. Sewing pattern is straight
stitch
Needle
zigzagging 2. Refer to "# 2-2"
does not
operate
# 23. 1. Malfunction of harness
The UP|
display 2. Malfunction of synchronizer
remains
without
changing
even when
the machine
pulley is
turned to the
needle up
stop position.
8-33
Check/repair/adjust
Returned to the neutral position, set the display so that
5Et appears, and then press the SET key. Operation
will return to the normal when the power is turned on.
Adjust so that the treadle is at the neutral position
when it is not being depressed.
Check P7 (PEDAL) connector is securely plugged in
on the control circuit board and one's harness is not
damaged.
Turn off the power and then turn the power back on.
Check P4 (PANEL) connector is securely plugged in
on the control circuit board and one's harness is not
damaged.
Check P3 (SYNC) connector is securely plugged in on
the control circuit board.
Use correct machine motor pulley
Turn OFF DIPSW1-2 and reset all.
Refer to "# 10. EE2"
Turn the machine pulley to check whether the upper
shaft is locked or not.
Check P-ROM securely plugged in on the control circuit
board.
Check DSW2-8 is turned OFF.
When release key lock turn OFF DSW2-8.
Check the setting of Max. sewing speed.
Refer to instruction manual "5-16. Adjusting the
treadle" (page 44).
Check P7 connector is securely plugged in on the con-
trol circuit board.
Check the sewing pattern
Check P3 (SYNC) connector is securely plugged in on
the control circuit board.
LZ2-B855E,B856E
Parts to be
replaced
Panel
Synchronizer
P-ROM,
control circuit board
Panel circuit board
Treadle unit
Treadle unit
Synchronizer
Synchronizer