Brother MFC-9420CN Service Manual page 300

I-20 Insufficient Gloss
Phenomenon
Gloss of the print is not sufficient as shown in
Main Causes
(1) The fuser roller is deteriorated.
(2) The fusing temperature is not properly controlled.
(3) The mode setting of the paper is not correct.
Countermeasures
(1) Replace the fusing unit FU with a new fusing unit FU.
(2) Confirm the mode setting (ordinary paper or thick stock) of the paper.
print sample [20] of Fig.9-1.
Fig. 9-21
9 - 4 4
Fusing Unit FU
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