Brother BAS-311E Service Manual page 111

Error status Probable causes
4. Fuse has blown
5. Power supply circuit board
defective
#1
continued
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.
BAS-311E.311EL.326E.326EL
Chapter 7
Parts to be replaced
Fuse 6A-250A
Power supply
circuit board
Control circuit
board
Panel circuit board
103