Brother HL-3400CN Series User Manual page 198

4. Remove the Back caps (2 pieces) of the Lower Tray Unit. Push down lightly on the
cap and then slide to the rear of the printer to remove them.
5. Use the handholds of the Duplex Unit to lift the Duplex Unit up.
Note
Ensure that the Duplex Cover Top Assembly is aligned and latched
straight with the lower part of the duplex unit.
6. Insert the fixing pins at either side of the Duplex Unit into the installation grooves in the
Lower Tray Unit.
Fig.5-51 Insert the Fixing Pin to the Installation Groove
Note
Make sure that the Rear Cover of the Lower Tray Unit is closed.
Fig.5-49 Removing the Back Caps
Fig.5-50 Hold the Duplex Unit
CHAPTER 5 MAINTENANCE
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