Brother HL-3400CN Series User Manual page 196

Note
Do not load B5 or smaller size paper and envelopes in the cassette loaded
into the optional Lower Tray Unit. It may cause paper jams.
How to Clear Paper Jams in the Lower Tray Unit
Paper Jam in the Cassette
1. When a Paper Jam has occurred in the Media Cassette, remove the Media Cassette
from the printer. Pull the Cassette out, slightly lift it and then pull the cassette from the
printer.
2. Remove the jammed paper and reinstall the cassette into the printer.
Paper Jam at the Rear of the Lower Tray Unit
1. When a Paper Jam has occurred at the rear of the Lower Tray Unit, open the Rear
Cover of the Lower Tray Unit.
2. Remove the jammed paper and close the Rear Cover of the Lower Tray Unit.
CHAPTER 5 MAINTENANCE
5-39