Brother LZ2-B855E Service Manual page 91

Error Probable causes
status
1. Malfunction of pulse motor
# 3.
Ec2
and harness
2. Malfunction of control circuit
board
1. Malfunction of cooling fan
# 4.
Ec3
2. Blocked air inlet in control
box filter
3. Malfunction of thermal sensor
on control circuit board
Cooling fan 1 or one's harness
# 5.
Ec4
problem (When looking from
the rear, right-side fan)
# 6. Cooling fan 2 or ones harness
Ec5
problem (When looking from
the rear, left-side fan)
# 7. 1. P-ROM poor connection
Ec7
2. Custom data problem
# 8. 1. P-ROM poor connection
Ec8
2. Malfunction of control circuit
board
3. P-ROM version mismatch
Malfunction of power supply
# 9.
EE1
circuit board
# 10. Abnormal rise in power supply
EE2
voltage
# 11. 1. Abnormal drop in power supply
EE3
voltage
2. Malfunction of harness
# 12. 1. Timing belt is not fitted
EE4
2. Pulley is loosened
3. Malfunction of synchronizer
or one's harness
4. Abnormal rise in power supply
voltage
5. Malfunction of machine motor
connector
# 13. 1. Broken fuse on the control
EE5
circuit board
2. Malfunction of harness
3. Malfunction of connection
Check/repair/adjust
Separate P16 (NPM) connector on the control circuit
board, and measure the resistance on the harness.
If the resistance is 1.5 - 2 Ω, there is problem.
Control circuit board
Check threads are not tangled in the cooling fan.
Clean the ventilation outlet of the control box.
Check the thermal sensor on control circuit board is
installed correctly and one is not blown.
a. Check P13 (FAN1) connector is securely plugged in
on the control circuit board.
b. Check threads are not tangled in the cooling fan 1.
a. Check P1 (FAN2) connector is securely plugged in
on the control circuit board.
b. Check threads are not tangled in the cooling fan 2.
Check P-ROM connector is securely plugged in on the
control circuit board.
Check the custom data is created
Check that the custom data is within the allowable
sewing area.
Check P-ROM connector is securely plugged in on the
control circuit board.
If the display remains even after the power is turned
off and back on again, thee is a malfunction in the
control circuit board.
Mismatch between control circuit board and PROM
versions
a. Check that the power supply voltage at the wall
outlet is within 10% of the rated voltage.
b. If a transformer has been connected, check the
transformer wiring. (Refer to the transformer wiring
diagram.)
Refer to "# 10. EE2"
Check P6 (POWER) connector is securely plugged in
on the control circuit board.
Fit the timing belt.
Adjust and fix pulley.
Check P3 (SYNC) connector is securely plugged in on
the control circuit board.
Refer to "# 10. EE2"
Check connection of the machine motor connector
Check the fuse F1 on the control circuit board is not
damaged.
Check P20 (AC17V/AC30V) connector is securely
plugged in on the control circuit board.
Check 4P connector from transformer is securely
plugged in on the power supply circuit board. ( See
below)
For 100V,200V === CN2(200V)
For 110V,220V,240V,380V,400V,415V === CN3(220V)
For 230V === CN4(230V/240V)
LZ2-B855E,B856E
8. ELECTRIC COMPONENTS
Parts to be
replaced
Pulse motor
Control circuit board
Control circuit board
DC fan motor 1
DC fan motor 2
Control circuit board
P-ROM
P-ROM
Control circuit board
P-ROM
Power supply circuit
board
Power supply circuit
board
Synchronizer
Fuse
8-32