The first locomotives entered service in 1980 and were an immediate success, ending a decade of uncertainty on the Northeast Corridor.

Amtrak assumed control of almost all private sector intercity passenger rail service in the United States on May 1, 1971, with a mandate to reverse decades of decline.

[3] To operate these trains, Amtrak inherited a fleet of 300 locomotives (electric and diesel) and 1190 passenger cars, most of which dated from the 1940s–1950s.

[4] Operation on the electrified portion of the Northeast Corridor was split between the Budd Metroliner electric multiple units and PRR GG1 locomotives.

[16] A pair of Faiveley DS-11 two-stage pantographs, one at each end of the locomotive, collected power from the overhead catenary wire.

[17] Thyristor converters stepped down the high-voltage AC to provide DC power at a much lower voltage to four traction motors, one per axle.

[14] A separate static converter supplied 500 kW 480 V head-end power (HEP) for passenger comfort.

The power modules used water-cooled insulated-gate bipolar transistor (IGBT) technology and provided about 5,000 kilowatts (6,700 horsepower) of traction power plus 1,000 kilowatts (1,300 horsepower) of HEP, twice the HEP capacity of the original DC units.

Five groups bid on the contract: General Motors' Electro-Motive Division (EMD)/ASEA, Morrison–Knudsen/Alstom, Brown Boveri, Siemens/KraussMaffei, and AEG/KraussMaffei.

MARC ordered four in 1986 for use on its Penn Line service on the Northeast Corridor between Washington, D.C., and Perryville, Maryland.

Alstom supplied AC propulsion equipment, electrical cabinets, transformers, HEP, and cab displays.

The rebuild provided Amtrak with locomotives that had improved high end tractive effort and performance with longer trains.

942 and 946, made their final run on June 18, 2016, on a special farewell excursion that ran between Washington, D.C., and Philadelphia.

[40] While Amtrak was replacing its AEM-7s, MARC initially decided in 2013 to phase out its electric operations on the Penn Line altogether and retire both its AEM-7 and Bombardier–Alstom HHP-8 locomotives,[41] but the railroad instead started a refurbishment program for its HHP-8s in 2017.

[42] SEPTA continues to use electric traction, replacing its seven AEM-7s and lone ABB ALP-44, an improved AEM-7, with fifteen ACS-64s.

[50] 15 AEM-7s entered storage at the Seaview Transportation Company in Rhode Island amid potential interest from the MBTA.

[51] Caltrain, which operates commuter trains in the San Francisco Bay Area, purchased two retired Amtrak AEM-7s to test their electrification system once completed.

[52] On June 7, 2018, the board awarded two contracts totalling approximately $600,000: one to purchase two AEM-7ACs from Mitsui & Co, and the other to Amtrak for refurbishment, training, and transportation to the Caltrain maintenance facility in San Jose.

[55] The seven SEPTA AEM-7s were leased to NJ Transit beginning in late December 2018 for the purpose of allowing NJ Transit to roster additional locomotives equipped with positive train control (PTC) in order to meet a deadline for operating PTC-capable equipment.

SEPTA then used them exclusively for overnight work service during autumn, cleaning tracks and applying traction gel.