The inquiry focused on 10 vehicle fires, eventually leading to a recall after as many months.

The National Highway Traffic Safety Administration has closed its investigation into a spate of Jeep Cherokee fires.

The inquiry had been prompted by two incidents filed in the NHTSA complaint database on the same day. In one highly publicized occurrence, an owner noticed an 'oily smell' before the vehicle experienced an engine-compartment fire, with "flames 20 feet high," that completely destroyed the vehicle.

The timing was particularly unfortunate for Fiat Chrysler Automobiles, as several of its brands had recently ranked at the bottom of Consumer Reports rankings. The Cherokee had been deemed the least reliable new SUV in the segment.

Two months after receiving the investigation notice from the NHTSA, FCA acknowledged four failures but dismissed the incidents as "random and isolated occurrences of under hood fire" rather than evidence of a potential defect.

After several months passed and the NHTSA pressed for more information regarding FCA's technical analysis, the company continued to receive reports of additional 'events.' Finally, after the sixth failure, the company determined that the A/C line routing had been botched during the assembly process, allowing the line to be cut or thermally degraded by the exhaust manifold heat shield.

A recall was issued 10 months after the first complaints were submitted to the NHTSA. After reviewing the fix campaign, the agency is satisfied with the resolution and has closed its inquiry.