3Com NETBuilder II, Installing Instruction, Page: 25 / 82

Maintenance and Repair 1-15
8 Reinstall the bracket containing the new floppy disk drive in the chassis.
a The two keyhole slots in the bottom of the bracket align with two locking
pins on the bottom of the chassis. Slip the wide part of the keyhole slots
over the pins.
b Slide the bracket toward the front of the chassis until it locks in place.
c From the front of the chassis, reinstall the two screws that secure the bracket
to the chassis.
d From inside the chassis, reinstall the screw on the back of the bracket.
9 Reconnect the ribbon cable and the power wiring harness to the connectors on
the back of the floppy disk drive.
10 Reinstall the front panel.
a Tip the top edge of the panel slightly away from the chassis, and align the
tabs on the bottom with the hinges at the bottom of the chassis.
b Push the front panel against the chassis.
c From inside the chassis, reinstall the two screws that secure the panel to the
chassis.
11 Reinstall the cover.
a Position the cover slightly behind the front of the chassis.
b Lower the cover and slide it toward the front of the chassis so that it
engages the front panel.
c Secure the cover with the screws you removed earlier from the back and
sides of the chassis.
12 If your system was previously mounted in a rack, reinstall the rack-mount
brackets on the chassis and remount the system.
13 Make sure the power switch is off (O is pressed down). Plug the power cord
into the power supply and the outlet.
14 Turn on the system.
Replacing the Backplane To replace the backplane in the 4-Slot chassis, follow these steps. You will need
a short #1 Phillips screwdriver.
1 Turn off the system and unplug the power cord from the outlet and power
supply.
2 If your system is mounted in a rack, remove it from the rack and remove the
rack-mount brackets from the chassis.
3 Remove the cable strain-relief bracket, if it is installed.
4 Remove the main processor module and all I/O modules from the chassis.
Loosen the thumbscrews and push the ejector levers open to remove
the modules.
5 Remove the cover from the chassis.
a Remove the screws from the back of the chassis and sides of the chassis.
b Slide the cover toward the back of the chassis and lift it off.