Brother BAS-311E Sewing Machine User Manual


 
103
BAS-311E.311EL.326E.326EL
Chapter 7
#1
continued
Probable causes
4. Fuse has blown
5. Power supply circuit board
defective
6. Control circuit board defective
7. Panel circuit board defective
Check/repair/adjust
Remove fuses No.3 and No.4, and check them for
continuity.
If there is no continuity, replace the fuses with new
ones, and perform the check/repair/adjust items of
#1-5.
Separate P4 (ACIN) connectors on the power supply
circuit board, and then measure the resistance
between the followin oth cases, the power supply
circuit board is not defective.
Measure the resistance between pins 1 and 2.
If there is not short, the power supply circuit board is
not defective.
rejoin P4 (ACIN) connectors on the power supply
circuit board.
Separate P3 (POWER) connectors on the main circuit
board, turn on the power, and measure the voltage
across pins 1 and 3 in the connector on the cable.
If it is + 5V, the power circuit board is not defective.
After measurement, turn off the power wait at least 5
minutes, and then rejoin P3 connectors.
With P3 (POWER) connectors plugged in on the
control circuit board, turn on the power, and measure
the voltage across pins 1 and 3 in the connector on
the cable.
If it is + 5V, the power circuit board is not defective.
After measurement, turn off the power.
Check that P18 (PANEL) connectors of the main circuit
board and P5 (DRV) connectors of the panel circuit
board are plugged in.
Parts to be replaced
Fuse 6A-250A
Power supply
circuit board
Control circuit
board
Panel circuit board
Error status