The National Highway Traffic Safety Administration is upgrading its investigation into Ford Motor Co.'s hands-free technology — called BlueCruise — after two fatal crashes involving all-electric Mustang Mach-E vehicles when the technology was in use.

Regulators said this week they are moving the status of the probe to "engineering analysis," a step needed before it could order a recall. The analysis will cover 2021-24 model years, which is about 129,222 cars, according to NHTSA.

In its analysis, NHTSA will investigate Ford's system limitations and "evaluate drivers’ ability to respond to scenarios that exceed system limitations," NHTSA said in documents. During the analysis, regulators will evaluate vehicles equipped with BlueCruise, review additional technical information, and perform additional analysis of related crashes and noncrash reports, it said.

Ford spokeswoman Amy Mast told the Free Press, "We are working with NHTSA to support its investigation."

The BlueCruise system uses a camera-based driver monitoring system to determine driver attentiveness. It is available on 97% of U.S. and Canadian highways on stretches with no intersections or traffic signals. Ford introduced the technology in model year 2021 and made it available in certain Ford and Lincoln vehicles.

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Investigation started last year

NHTSA said it opened its investigation into BlueCruise in April 2024 after it received notice of two fatal accidents that involved BlueCruise-equipped Mach-Es. Based on those crashes, NHTSA started investigating the 2021-24 model year Mach-E vehicles equipped with BlueCruise.

According to a Reuters report last year, in February, a Ford Mustang Mach-E driver in San Antonio was using BlueCruise when the Mach-E rear-ended a stationary Honda CR-V on a highway, killing the 56-year-old Honda driver. BlueCruise also may have been in use in a second fatal crash, between a Mach-E and two stationary cars in Philadelphia in March, Reuters reported. In that incident, the Mach-E hit two stationary vehicles on the highway, killing two people.

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In June 2024, regulators asked Ford to provide information pertaining to both crashes, noncrash reports and technical specifications that relate to BlueCruise, as well as other Ford partial driving automation systems that offer lane and speed maintenance, NHTSA said in a statement.

NHTSA found limitations in the technology

In its response to NHTSA's request, the agency said Ford told it there are about 2.5 million Ford and Lincoln vehicles equipped with a partial driving automation system such as Lane Centering Assist, which is a hands-on partial driving automation system, and Adaptive Cruise Control.

NHTSA said the vehicles with BlueCruise, the focus of this investigation, have lane-centering assist capability and offer hands-free driving, but only on certain roadways. System availability is geofenced using vehicle GPS.

For BlueCruise- and lane-centering assist-equipped vehicles, both adaptive cruise control and Pre-Collision Assist features use a combination of camera and radar-sensing technologies to detect and classify objects, NHTSA said.

"Adaptive cruise control is specifically designed to detect vehicles (including cars, trucks and motorcycles) and bicycles in front of the subject vehicle which are either stationary or moving in the same direction as the subject vehicle," NHTSA said in its statement.

Regulators said its investigation had found limitations in the detection of stationary vehicles in certain conditions.

"Specifically, due to the potential for false detection of stationary objects at long distances, Ford designed Adaptive Cruise Control to inhibit any response to reported stationary objects when the subject vehicle’s approach speed is at or above 62 mph," NHTSA wrote. "Additionally, system performance may be limited when there is poor visibility due to insufficient illumination."

More crashes discovered

In both fatal collisions, the Mach-E vehicle was traveling over 70 mph on a highway at night in BlueCruise mode and crashed into a stationary vehicle, NHTSA said. Data from the vehicles’ event data recorders showed the drivers did not apply brakes or take evasive steering action, and no deceleration was initiated by either the BlueCruise system or Pre-Collision Assist before impact.

Through the agency’s crash analysis, it found four additional frontal crashes where a Ford vehicle hit a stopped or slow-moving car or another stationary object. Two of these involved BlueCruise-equipped Ford Mustang Mach-Es.

Based on NHTSA’s analysis, it said system limitations relating to the detection of stationary vehicles while traveling at highway speeds and in nighttime lighting appear to be factors in collisions under investigation and some "near-miss, non-crash reports," it wrote. The agency said it will further investigate these limitations and drivers' ability to react to such scenarios.

Jamie L. LaReau is the senior autos writer who covers Ford Motor Co. for the Detroit Free Press. Contact Jamie at [email protected]. Follow her on Twitter @jlareauan. To sign up for our autos newsletter. Become a subscriber.