Brother HL-2400C Service Manual page 268

Error Code
Concerned Part Developer Motor(DM)
Is there any unusual rotation noise while printing ?
NO
Check the connector.
Is ECN15 of IOD2 properly connected with the connector of DM1?
YES
Is ECN1 of IOD2 properly connected with DCN9 of IOD1?
YES
Is ECN1 of IOD2 properly connected with I2CN of MCTL?
Check the voltage: +24V-1 and +5V-1.
+24V-1: Is there +24V between DM1-4 and 5,ECN15-4 and 5, ECN2-5 and 8 ?
+5V-1: Is there +5V between DM1-6 and 7,ECN15-6 and 7, ECN2-11 and 12 ?
NO
Replace the IOD2 PCB.
Is E1 error cleared ?
NO
Replace the IOD1 PCB.
Is E1 error cleared ?
YES
Finished
E1
YES
NO
NO
YES
YES
NO
Replace the toner cartridge.
Is the noise cleared ?
NO
Replace developer gear unit and motor.
Connect the connectors properly.
Is E1 error cleared ?
NO
Replace the developer motor.
Finished
LVPS
Replace the MCTL PCB.
YES
Finished
YES
Finished
MCTL
IOD2
12CN
DMRDY-N
DMCLK
1
11 11 ECN1
DMON-N
DMON-N
2
12
12
DMCLK
3
ECN
PGND
4
15
+24V-1
5
ECN2
IOD1
SGND
6
+24V-1
+5V-1
5 5
7
PGND
DCN9
NC
8
8
8
+5V-1
11 DMREV-N
11
9
SGND
12
12
DM1
1
2
3
4
5
DM
6
7
8
9