Fiat Chrysler says it is recalling 1.1 million vehicles, including 811,586 midsize SUVs and full-size cars in the U.S., to try to alleviate confusion about when the vehicle’s automatic transmissions are in the “park” position, which has resulted in 41 injuries.

Drivers have been getting out of the vehicles without shifting into park while the engine is still running. The problem involves vehicles with electronic shift levers on their consoles that spring back to the same position after being shifted. Drivers can’t tell by looking at the position of the shifter whether it is in “park.” They have to depend on indicator lights, Fiat Chrysler says.

In the U.S., The recall involves certain 2012 to 2014 Dodge Charger and Chrysler 300 sedans and 2014 and 2015 Jeep Grand Cherokee SUVs. The recall will include an estimated 52,144 vehicles in Canada, 16,805 in Mexico, and 248,667 elsewhere outside the U.S.

The recall results from an investigation by the National Highway Traffic Safety Administration, which was joined by Fiat Chrysler. It appears to have acted on complaints.

One owner in Walton, Ind., said they left their 2015 Jeep Grand Cherokee running when dropping off a DVD when they thought they had pushed the shifter in the right direction. “My 23-year-old son was in the passenger seat and yelled out, ‘Dad, the car is moving,” he wrote. “I jumped back in and put my foot on the brake and watched the shift indicator as I slowly moved the shifter up so it indicated ‘park.'”

The confusion also doesn’t appear to be limited to shifting the vehicle into park. A driver in Rochester Hills, Mich., says they became confused about whether vehicle was in reverse gear.

“Intending to back into my driveway, I shifted into reverse,” they wrote in their complaint. “The vehicle was not in reverse and crashed into the vehicle that was parked…across the street.”

One expert, Sean Kane of Safety Research and Strategies, a firm that researches car safety issues, says the problem involves a failure by engineers to fully anticipate all scenarios in which drivers use the shifters. In the past, automatic transmissions were mechanical and it was easier to make sure a car was in the correct gear. Now that they are electronic, it’s easier to become confused, which helps explain the accidents.

“It’s a high number of injuries,” Kane says.  “I think it’s a complete lack of human-factors engineering and a lack of built-in fail safes.”

Even though there are chimes and alert messages that sound when the driver’s side door opens while the engines are running while not in park, the automaker says the warnings may be insufficient. Fiat Chrysler says it will enhance the warnings and modify the settings in the transmission so the vehicle won’t move under certain conditions if it is in park.