Brother HL-2400C Service Manual page 260

Chart 8-4 Troubleshooting
Code Description of Error
1. Failure of MCTL PCB.
C3 NVRAM Error
Does the error repeat after turning the power switch on and off?
Does the error repeat after carrying out the "C3 Error Clearance Method" ?
Replace the failed MCTL PCB with a new one.
Code Description of Error
Hard Error of MCTL
C4
Control Circuit.
Does the error repeat after turning the power switch off and on?
Replace the failed MCTL PCB with a new one.
Cause of Error
1. Turn off and on the power switch.
• CPU
2. If method 1 does not work, carry out the "C3 Error Clearance Procedure".
• EEPROM
3. Replace the failed MCTL PCB with a new one.
C3
YES
YES
Cause of Error
1. Failure of MCTL PCB. 1. Turn off and on the power switch.
2. Replace the failed MCTL PCB with a new MCTL PCB.
C4
YES
Clearance Method
NO
The printer is OK.
NO
The printer is OK.
Clearance Method
NO
The printer is OK.