The magazine argues that it should be reprogrammed to require drivers to keep their hands on the wheel.

Consumer Reports has stepped up pressure on Tesla Motors to disable its Autopilot system until the system can be modified with several safety provisions.

In a report titled "Too Much Autonomy Too Soon," the magazine argues that Tesla's marketing is contradictory and potentially misleading. The company has promoted its Autopilot technology as capable of advanced autonomous operation, yet drivers are warned that it is a 'beta' technology and they must remain in control of the car at all times.

"'Autopilot' can't actually drive the car, yet it allows consumers to have their hands off the steering wheel for minutes at a time," said CR's VP of consumer policy, Laura MacCleery. "Tesla should disable automatic steering in its cars until it updates the program to verify that the driver's hands are on the wheel ... Consumers should never be guinea pigs for vehicle safety 'beta' programs."

The magazine has also pressured the National Highway Traffic Safety Administration to "step up" its oversight of cars with active safety features. The authors call for mandatory safety standards for such technology, validated via third-party testing and certification.

Tesla has rejected calls for the system to be shut down while the NHTSA completes its ongoing investigation into the first fatal Autopilot crash, arguing that only one confirmed death has occurred in more than 130 million miles of Autopilot-assisted driving.

"Tesla is constantly introducing enhancements, proven over millions of miles of internal testing, to ensure that drivers supported by Autopilot remain safer than those operating without assistance," the company said in a statement. "We will continue to develop, validate, and release those enhancements as the technology grows. While we appreciate well-meaning advice from any individual or group, we make our decisions on the basis of real-world data, not speculation by media."