In a tweet on Friday, Tesla CEO Elon Musk said the company had started rolling out an over-the-air software update for its Model 3 electric cars to address a problem with their braking performance, a problem revealed by Consumer Reports last week.

In the tweet, Musk said the update should improve braking "by ~20 ft for repeated heavy braking events."


Consumer Reports had tested the car and had released its results last week. In its review, the magazine said it could not recommend the car because of its inconsistent braking performance, and emergency stops that took longer than a Ford F-150 pickup on average.

Echoing results from Car and Driver tests, the organization said that the only time the Tesla Model 3 performed better in its emergency braking tests was on its very first stop from 60 mph.

In response to the criticism from Consumer Reports, Musk had said that the company would ensure that all Model 3s had "excellent" braking, even if that meant recalling all existing Model 3s for a hardware fix.

In a conversation last week with Consumer Reports' director of auto testing, Jake Fisher, Musk said the problem had been traced to the car's braking control system. That is the system that received a firmware update over the air this week.

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Fisher said the magazine will retest its Model 3 after it receives the firmware update, and release new results. "If Tesla can update the brakes over the air, we will retest our Model 3," Fisher said. "It would be an industry first if they could improve brake performance remotely."

In the same chain of tweets, Musk said that Performance versions of the Model 3 will come with more powerful brake hardware, though all-wheel-drive models will not. The company recently opened orders for both of these more expensive versions of the Model 3, and deliveries are expected to begin in July.

He also said that all-wheel-drive versions will have higher levels of regenerative braking that will work right up to the traction limits of standard Model 3's tires. Tesla Model 3 Performance editions will have more aggressive tires with even more traction.