Brother HL-3450CN Service Manual page 292

Error Code
Concerned Part Main Motor(MM)
Does a belt cartridge rotate lightly ?
YES
Does a fuser unit rotate lightly ?
YES
Confirm the connection of connector.
Is ECN12 of IOD2 properly connected with connector of DM1 ?
Is ECN2 of IOD2 properly connected with DCN10 of IOD1 ?
Is ECN1 of IOD2 properly connected with 12CN of MCTL ?
YES
Check the voltage:+24V-1 and +5V-1.
+24V-1: Is the voltage +24V between MM1-4 and 5, ECN12-4 and 5, ECN2-5 and 1 ?
+5V-1: Is the voltage +5V between MM1-6 and 7, ECN12-6 and 7, ECN2-7 and 1 ?
NO
Replace the IOD2.
Is E2 error cleared ?
NO
Replace the IOD1.
Is E2 error cleared ?
YES
Job is complete.
E2
NO
NO
NO
YES
YES
NO
Replace the belt cartridge.
Replace the fuser unit.
Is E2 error cleared ?
NO
Replace developer gear unit and motor.
Is E2 error cleared ?
NO
Replace the main motor.
YES
Is E2 error cleared ?
MCTL
12CN
Job is complete.
IOD1
DCN10
Replace the MCTL PWB.
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HL-3450CN SERVICE MANUAL
YES
Job is complete.
YES
Job is complete.
Job is complete.
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28
MM1
IOD2
MMCLK
MMRDY-N
7
7
1 1
ECN1
MMON-N
MMON-N
8
8
2
2
MMREV-N
MMCLK
9
7
3 3
MMENC
10
PGND
10
4 4
ECN12
+24V-1
6
ECN2
5 5
SGND
+24V-1
6 6
1
+5V-1
1
PGND
7 MMENC 7
5
5
+5V-1
8 8
MMREV-N
7
7
SGND
9 9
9
9
MM