Brother HL-3450CN Service Manual page 283

CHAPTER 8 TROUBLESHOOTING
Code Description of Error
C3 NVRAM Error
Does the error repeat despite of implementing "On/Off of Power Switch" ?
Does the error repeat despite of implementing "NVRAM INITIAL" ?
Replace the failed MCTL PWB with a new one.
Code Description of Error
Hard Error of MCTL
C4
Control Circuit.
Does the error repeat despite of implementing "On/Off of Power Switch" ?
Replace the failed MCTL PWB with a new one.
Cause of Error
1. Failure of MCTL PWB 1. Turn on and off the power switch.
CPU 2. Above method 1 does not work, implement "C3 Error Clearance Procedure".
EEPROM
3. Replace the failed MCTL PWB with a new one.
C3
YES
YES
Cause of Error
1. Failure of MCTL PWB. 1. Turn on and off the power switch.
2. Replace the failed MCTL PWB with a new one.
C4
YES
Clearance Method
NO
Continue to drive the engine.
NO
Continue to drive the engine.
Clearance Method
NO
Continue to drive the engine.
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