(Reuters) -The National Highway Traffic Safety Administration on Friday upgraded its investigation into nearly 1 million Stellantis' ( STLA ) Dodge brand vehicles to an engineering analysis from a preliminary evaluation over faulty door locks and windows.

The analysis involves certain Dodge Journey crossovers built between 2009 and 2020.

Stellantis ( STLA ) did not immediately respond to a Reuters request for a comment.

An engineering analysis is a mandatory requirement before the auto safety regulator can potentially demand a recall.

The NHTSA said there were seven incidents of door and window malfunction in the model, including one fatality.

"Inoperative door locks and windows may prevent vehicle occupants from exiting the vehicle during an emergency," the NHTSA said.

(Reporting by Nathan Gomes in Bengaluru; Editing by Nivedita Bhattacharjee and Shinjini Ganguli)