Brother MFC-9130CW Service Manual page 92

■ Error code 6400
No Belt Unit
Open the Top Cover, pull out all 4 Drum Units completely and install the Belt
Unit.
The registration mark sensor detected that no belt unit was set.
<User Check>
- Re-insert the belt unit.
Step
1 Registration mark L PCB
harness connection failure
2 Eject sensor PCB harness
connection failure
3 Eject sensor PCB failure
4 Registration mark L failure
5 Main PCB failure
■ Electrodes location of belt unit
Cause
Fig. 2-10
2-53
Remedy
Check the registration mark L PCB
harness connection and reconnect it.
Check the eject sensor PCB harness
connection and reconnect it.
Replace the eject sensor PCB ASSY.
Replace the Registration mark L PCB
ASSY.
Replace the main PCB ASSY.
Confidential