Fiat Chrysler has recalled more than 1.1m cars and SUVs worldwide because they may roll off after drivers leave the vehicles.
The Italian-American carmaker said as many as 41 injuries are linked to the recall in incidents where motorists assumed the vehicles had been placed in park mode.
The 2012-2014 Dodge Charger and Chrysler 300 sedans and 2014-2015 Jeep Grand Cherokee sport utility vehicles are covered by the recall.
About 811,000 vehicles in the US are affected, along with about 52,000 in Canada.
Nearly 17,000 more are in Mexico and almost 250,000 vehicles are outside North America.
Fiat Chrysler said it will fix the vehicles to keep them stationary under certain circumstances, even when the driver fails to put them in park mode.
But it is not clear when the remedy will be available.
The US National Highway Traffic Safety Administration (NHTSA) said testing of the vehicles’ electronic gear shifter found it was “not intuitive”.
The agency said it “provides poor tactile and visual feedback to the driver, increasing the potential for unintended gear selection”.
The NHTSA said it was “clearly a safety issue that has led to hundreds of crashes and dozens of injuries”.
It said in February it had reports of 314 complaints, including 121 crashes after vehicles rolled away, some striking buildings, drivers or other cars.
Three people suffered fractured pelvises while four others required hospital treatment.
In September 2015, a new Jeep Grand Cherokee in Leonardtown, Maryland, rolled away and hit headstones in a cemetery, causing $1,500 of damage.
NHTSA spokesman Bryan Thomas said the agency “will be monitoring this recall carefully to ensure that (Fiat Chrysler) produces a safe solution and gets the vehicles remedied as quickly as possible”.
Fiat Chrysler – the world’s seventh-largest automaker – said it began equipping the affected vehicles with a new shift-lever design in 2015.
Many of the crashes occurred soon afterwards.
In July last year, Fiat Chrysler recalled 1.4 million vehicles in the US, after hackers proved they could take control of an SUV over the internet and drive it into a ditch.