A testing pluggable module includes a pluggable body extending between a front end and a mating end defining a mating interface with a communication connector of a receptacle assembly. The mating end is receivable in a module cavity of the receptacle assembly to mate with the communication connector. The pluggable body has an exterior forward of the mating end. The testing pluggable module includes an internal circuit board held in the pluggable body having a testing circuit operating at least one testing function. The testing pluggable module includes a user interface on the exterior of the pluggable body. The user interface has an input configured to operably control the at least one testing function of the testing circuit.