"Cruise is resuming manual driving to create maps and gather road information in select cities, starting in Phoenix. This work is done using human-driven vehicles without autonomous systems engaged," the company said in a blog post.
The company had suspended its U.S. operations last October after a pedestrian in San Francisco hit by another car was dragged by one of its robotaxis.
After the incident, Cruise's permit to operate in California was suspended and the National Highway Traffic Safety Administration issued a recall of its vehicles.
Cruise said the move to resume human-driven cars was key to validate its self-driving systems in its path to return to driverless operations, adding that it plans to expand this effort to other cities.
Its rival and Alphabet's (GOOGL.O) self-driving startup Waymo has been operating and expanding services in Phoenix for several years and recently began offering driverless rides on freeways in the Arizona city.
Waymo has also partnered with ride-hailing platform Uber Technologies (UBER.N) to provide the city's residents with autonomous, electric rides with no human driver behind the wheel.
Under Cruise's former CEO Kyle Vogt, company officials had said their decision to focus on San Francisco would deliver a more robust autonomous vehicle technology than developing software on the broad boulevards of a city like Phoenix.
Cruise said during the operational pause over the last few months, it has been conducting extensive tests in complex environments and on closed courses to ensure continuous retraining and improvement.
