Brother DCP-L8400CDN Service Manual page 221

(3) Remove the Front cover release button spring from the Front cover.
Assembling Note:
When assembling the Front cover release button spring, attach "A" of the Front cover
release button spring to the cutout of the Front cover release button.
Front cover
release button spring
Fig. 3-47
Front cover release button
Fig. 3-48
3-57
Front cover
Boss
Front cover
release button spring
"A"
Cutout
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