Two months after federal safety regulators expanded their investigation into Fiat Chrysler vehicles after receiving more than 100 complaints about crashes and injuries resulting from drivers inadvertently leaving their vehicles in gear with the engine running, the carmaker is officially recalling 811,000 SUVs and sedans equipped with the confusing electronic gear shifter. 

Fiat Chrysler announced Friday that it would recall 811,586 model year 2012 to 2014 Dodge Charger and Chrysler 300 sedans and model year 2014 to 2015 Jeep Grand Cherokee SUVs in order to alleviate confusion about when the vehicle’s transmissions are in the “park” position.

The carmaker says the recall was initiated to “enhance” warnings and transmission shift strategy after an investigation by the National Highway Traffic Safety Administration and Fiat Chrysler found some drivers have exited their vehicles without first selecting “PARK.”

According to a notice [PDF] filed by NHTSA, the investigation, which was first opened in August 2015, centers on vehicles equipped with Monostable electronic (E-shift) gearshifts.

The shift system in the affected vehicles operates electronically and the gear requested by the driver is transmitted from the shifter via the CAN Bus to the Transmission Control Module which makes the requested shift.

However, in some vehicles, the gearshift doesn’t actually move, but springs back to a centered or neutral position.

If a driver opens his or her door when the gearshift isn’t in “park,” a chime rings and a message pops up to alert them that the transmission is not in “park.”

The engine also will not turn off normally without the transmission in “park.”

“This function does not protect drivers who intentionally leave the engine running or those who do not realize that the engine is still running after an attempted shut-off,” investigators said in February.

As a result, drivers may exit the vehicle when the engine is running and the transmission is not in “park,” leaving the unattended vehicle to roll away, NHTSA states.

So far, the company says it is aware of 41 injuries related to the issue. Vehicles involved in those incidents were inspected and no evidence of equipment failure was found.

NHTSA’s Office of Defects Investigation previously announced it was aware of 314 consumer complaints about the issue, 267 submitted to Fiat Chrysler and 69 submitted via NHTSA’s database.

In all, investigators identified 121 incidents that have resulted in crashes or fires, with 30 incidents involving injuries to drivers or passengers such as a broken nose, facial lacerations requiring stitches, sprained knees, severe bruising, and trauma to legs.

“While in ‘park’ and idling, the vehicle rolled forward and struck objects 20 yards away causing $1,500 worth of damage to the right front bumper,” one complaint states. “My wife parked the car and had exited the vehicle, when after about 30 seconds it rolled forward and struck headstones in a cemetery. The car still indicated it was in ‘park’ when my son reentered the vehicle.”

In another complaint, the owner of a 2014 Jeep Grand Cherokee says the vehicles rolled from the “park” position without warning. When the woman attempted to stop the car, it ran over her hip, causing injuries that required medical attention.

Owners of affected Charger and Chrysler 300 vehicles offered similar experiences to NHTSA.

“When I put the car into ‘park,’ it pops into reverse,” the owner of a Chrysler 300 writes in a complaint. “Then I hit the engine off button, but since it is in reverse, the engine stays on. Then I open the door to get out, thinking the engine is off and the car is in ‘park,’ and it starts rolling backward. This has happened six times.”

The carmaker said on Friday the upcoming enhancements will combine warnings with a transmission-shift strategy to automatically prevent a vehicle from moving, under certain circumstances, even if the driver fails to select “PARK.”

Owners of affected vehicles will be notified when service becomes available.

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