Brother DCP 8040 - B/W Laser - All-in-One Service Manual page 230

M-12 Engine PCB error
Possible cause Step
Fixing unit 1
ground wire
connection
Harness 2
connection
failure
Engine PCB 3
Main PCB 4
M-14 DIMM failure
Possible cause Step
DIMM failure 1
Check
Is the ground wire on the fixing
unit secured with the shoulder
screw correctly?
Is the connection of the
connector between the main
PCB and the engine PCB
connected correctly?
Is the problem solved by
replacing the engine PCB?
Is the problem solved by
replacing the main PCB?
Check
Try installing DIMM into
another machine, then check
the memory size in Print
Settings.
Is it possible to print the data?
6-27
MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
Result Remedy
No Secure the ground wire
correctly with the shoulder
screw.
No Reconnect the connectors
securely.
Yes Replace the engine PCB.
Yes Replace the main PCB.
Result Remedy
Yes Replace the main PCB.
No Replace the DIMM.
SERVICE MANUAL