Install and Upgrade Internal Modules and FieldReplaceable UnitsThe Cisco 1100 Series Integrated Services Routers have internal modules and field-replaceable units (FRUs)that can be quickly and easily removed and replaced without having to send the entire router for repair.This section describes how to install and upgrade the internal modules and FRUs in the Cisco 1100 SeriesISRs. The information is contained in the following sections:• Access Internal Modules, on page 1• Locate Internal and External Slots for Modules, on page 3• Install an LTE Pluggable Module, on page 3• Install and Remove Small Form Pluggable Modules, on page 10Access Internal ModulesTo access the internal modules on the router, you must first disconnect the power source and then remove thechassis cover. See the Replacing the Chassis Cover section for instructions on how to remove and laterreplace the chassis cover on the routers.Only trained and qualified personnel should be allowed to install, replace or service this equipment. Statement1030.WarningBefore opening the unit, disconnect the telephone-network cables to avoid contact with telephone-networkvoltages. Statement 1041.WarningPower off the unit before you begin. Statement 237.WarningInstall and Upgrade Internal Modules and Field Replaceable Units1