Specifications

Repair and Replacement 8-3
Replacing a Front Card
Save the electrostatic bag, foam, and carton. These packaging materials are needed to return the
failed part to Cisco.
Replacing a Front Card
This section describes how to replace an MGX 8220 front card.
The MGX 8220 shelf front cards are:
• MGX 8220 Shelf Controller (ASC)
• Broadband Network Module (BNM)
• Service Redundancy Module (SRM)
• Service Modules
• ATM Inverse Multiplexer Network Module (IMATM)
Caution Ground yourself before handling the MGX 8220 shelf cards by placing a wrist strap on your wrist
and clipping the wrist strap lead to the cabinet.
When a card has failed, the red FAIL light for that card turns on. Before replacing it, check to see if
the card needs to be reseated and check that the appropriate back card is correctly installed. After
reseating the card, wait for it to run its self-tests to see if the ACTIVE light comes on. If the card is
seated correctly, but the FAIL light is still on, replace the card.
When replacing a card that has no redundant equivalent, the service provided by that card will be
disrupted. Replacing a non-redundant ASC or BNM card will bring down the entire shelf. Replacing
a FRSM card will bring down the channels that are serviced by that card.
To remove a front card:
Step 1 Insert a small flat head screwdriver into the slot in the retaining tab and press until the latch
springs open.
Step 2 Gently pull the card out of the card cage.
To install a front card:
Step 1 Position the card guides over the appropriate slot at the top and bottom of the card cage.
Step 2 Gently slide the card all the way into the slot and press the retaining tab until it snaps into
the vertical position.
Replacing a Line Module
Back cards are retained through two screws: one at the top of the faceplate and one at the bottom of
the faceplate. Back cards contain very few active components (if any) and rarely need replacing.
To remove a back card:
Step 1 Remove any cables connected to the back card.
Step 2 Use a flat screwdriver to undo the two retaining screws in the back card’s faceplate.
Step 3 Pull the two extraction levers into the horizontal position. This will start the card extraction.
Step 4 Gently pull the card out of the card cage.