Brother HL-4040CN Service Manual page 26

Error code C9
DIMM Error
Make sure that the DIMM is inserted correctly.
Defective DIMM is installed.
User Check
- Check if the DIMM is installed correctly.
- Replace the DIMM with a new one.
Error code E0
Print Unable E0
Turn the power off and then back on again.
Program error
User Check
- Turn the power off and on.
Error code E1
Print Unable E1
Turn the power off and then back on again.
Program error
User Check
- Turn the power off and on.
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