Brother HL-3400CN Series User Manual page 214

When you install DIMMs, follow these steps:
1. Turn off the printer and unplug the power cord from the AC
outlet.
Note
Be sure to turn off the power to the printer before installing or removing
the DIMMs.
2. Unscrew the two screws securing the rear plate of the main
controller board and pull out the main controller board.
Fig. 5-73 Removing the Main Controller Board
3. Unpack the DIMM and hold it by its edge.
!
Caution
Do not touch the memory chips and the surface of the main controller
board. If static electricity collects, it may damage these electrical parts.
4. Hold the DIMM with your fingers against the side edges and
thumb against the back edge. Align the notches on the DIMM
with the DIMM slot. (Check that the locks on each side of the
DIMM slot are open, or outward.) .
Fig. 5-74 Install the DIMM
CHAPTER 5 MAINTENANCE
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