Brother MFC5100C Service Manual page 165

Recording paper
Check that:
(1) A recommended type of recording paper is used.
(2) The recording paper is not dampened.
Ink cartridges
(1) Check that all of four ink cartridges are loaded.
Print head
(1) Check that the print head is installed on the carriage correctly. (Check the dimple contact
between the print head PCB and the carriage PCB.)
(2) Repeat the head purging operation several times.
(3) Clean the print surface of the print head unit. (Refer to page 6-23.)
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