Brother MFC-9320CW Service Manual page 98

■ Error code 31
Print Unable 31
Turn the power off and then back on again.
Density sensor error (Incorrect measurement value of the density sensor)
Error code 32
Print Unable 32
Turn the power off and then back on again.
Density sensor shutter performance malfunction
<User Check>
- Check if there is a scratch, dirt or the like on the belt unit. If there is, replace the belt unit
with a new one.
Step
1 Harness connection failure of
registration mark L PCB ASSY
2 Harness connection failure of
density sensor shutter solenoid
3 Registration mark L PCB failure
4 Engine PCB failure
5 Main PCB failure
Cause
3-17
Remedy
Check the harness connection between
the registration mark L PCB ASSY and
registration mark relay PCB ASSY, and
the one between the registration mark
relay PCB ASSY and engine PCB ASSY.
Then, reconnect them.
Check the harness connection of the
density sensor shutter solenoid and
reconnect it.
Replace the registration sensor holder
ASSY.
Replace the engine PCB ASSY.
Replace the main PCB ASSY.
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