Apparatus is provided for remote testing of the condition of a telephone communication line to the point of interfacial connection between the line and customer equipment. The apparatus includes sensing means responsive to a trigger signal inserted onto the line at the telephone company end, the trigger signal being an alternating current tone burst of a given frequency, given minimum time duration, and given minimum voltage level. The sensed trigger signal activates a switch means at the point of customer interface, with the switch means in its quiescent, first condition maintaining the integrity of the line and in its second, activated condition disconnecting the line and inserting onto the line for a given period of time a given electrical impedance and a disconnect indicator. The sensing means is responsive to the presence of the trigger signal independent of the condition of any equipment beyond the point of customer interface when the switch means is in its first condition. Means for testing the condition of the telephone line with the given electrical impedance on the line are provided at the telephone company end of the line.