Brother BAS-311E Service Manual page 118

Chapter 7
Error status Probable causes
2. The control circuit board is
defective.
#13
The
machine
does not
operate for
sewing and
error [E.20]
appears.
1. When error code [E.20] appears
after the machine operates, the
synchronizer is defective.
#14
After the
2. When error code [E.20] appears
machine
after the machine operates, the
operates,
machine has been locked due to
an error
insufficient adjustment.
code
appears.
3. When error code [E.90] appears
after the machine operates, the
power supply voltage has
sharply dropped.
1. The synchronizer is defective.
#15
The
machine
cannot sew
patterns as
2. The feed mechanism does not
pro-
move as programmed.
grammed.
1. Mechanical adjustment is
insufficient.
2. The solenoid is defective.
#16
Thread
trimmer
and thread
wiper do
not
Thread wiper
Thread trimmer
operate.
3. The control circuit board is
defective.
Thread wiper
110
Red
Black
Thread trimmer
BAS-311E.311EL.326E.326EL
Check/repair/adjust
• Remove connector P15 (DC300) on the control
circuit board, and measure the resistance between
pins 1 and 2 in the connector on the control circuit
board.
(A digital meter can not be used.) Using X1K
range, the needle should indicate 10K
After measurement, return P15 to its original
position.
(If this measurement is not approved, check
control circuit board fuses nos. 2, 3, and 4. They
may be blown.)
• Check that connector P2 (SYNCHRO) on the
control circuit board is securely inserted and there
is no damage in the synchronizer cable.
• Turn the pulley manually to check it can easily
rotate.
• Refer to #1.1-5
If the power supply capacity per machine is 600VA
or more, the voltage sharply drops as soon as the
machine starts, resulting this error to appear.
• Refer to #14-1.
Even if the synchronizer is defective, the test
feeding will be performed correctly.
• Refer to #8-1, 2, 3, 4.
• Remove the covers. If the solenoids for thread
trimmer and thread wiper do not operate, check
the following items.
• Refer to #4-7. (When measuring for thread wiper,
turn on the thread wiper switch.)
• Remove connector P5 (SOL) on the control circuit
board, turn on the power, start sewing, and
measure the voltage across the following pins in
the connector on the control circuit board:
Pins 5 and 6 (thread trimming)
Pins 7 and 8 (thread wiper)
The voltage in each case should be output for an
instance at the end of sewing.
Parts to be replaced
Control circuit
board.
-30K .
Synchronizer
assembly
Synchronizer
assembly
Solenoid
Solenoid harness