The National Highway Traffic Safety Administration has opened what it calls a "recall query" after receiving eight reports of fires occurring after the recall fix was installed. No crashes or injuries were reported in the fires, according to the NHTSA documents.

In July 2014, FCA US, the former Chrysler, recalled about 900,000 Jeep Grand Cherokee and Dodge Durango SUVs globally from model years 2011 to 2014 to fix wiring for vanity mirror lights in sun visors to prevent potential short circuits and fires. Of those, 661,888 were in the United States.

In last year's recall, fires were caused by an electrical short in the vanity lamp wiring, according to the NHTSA documents. The remedy FCA developed consisted of a plastic guide way installed on each sun visor routing the wiring away from attachment screws.

Fiat Chrysler spokesman Eric Mayne said on Wednesday the automaker is cooperating in the new NHTSA probe and has reiterated service instructions for dealership technicians.

(Reporting by Ben Klayman in Detroit; Editing by Alden Bentley)