Since General Motors began recalling 2.6 million older small cars with defective ignition switches last year, federal regulators have been criticized for their failure to thoroughly investigate the problem despite receiving clear warnings from vehicle owners.
Now, there are signs that the National Highway Traffic Safety Administration, under a new administrator, Mark R. Rosekind, is quicker to look into potential defects based on owner complaints.
The agency recently opened five investigations into vehicles made by Ford, Fiat Chrysler and Mazda after receiving complaints from worried owners about problems with brakes, airbags and anti-collision systems. In one case, the investigation was begun after the agency received six complaints on its website.
An investigation can often lead to a recall.
The largest inquiry involves about 630,000 Jeep Wranglers from the 2007-12 model years after more than 200 owners complained about the airbag warning light illuminating, indicating the safety device would not work in a crash. There were no reports of accidents.
Four years ago, a similar problem resulted in the recall of 2008-12 Wranglers with right-hand drive. Those vehicles are used for export or postal service.
The second inquiry involves about 54,000 Mazda CX-9 sport utility vehicles from 2007-8, which are being investigated after reports that corrosion on the suspension could allow a wheel to break free.
“The passenger front wheel disconnected from the lower control arm, resulting in an immediate loss of control,” the owner of a Mazda CX-9 wrote in a complaint last August. “Fortunately, the vehicle was being driven through a residential area at a low speed.”
The agency report showed six complaints but no accidents.
In the third inquiry, about 20,000 Jeep Grand Cherokees from the 2014 model year are being investigated after nine owners said that the anti-collision system suddenly applied the brakes and slowed the vehicle “with no pending threats in the line of travel,” according to the report.
Such systems typically use radar and a camera to detect obstacles and can apply the brakes if the driver disregards both a warning on the dashboard and an audible alarm.
About 250,000 Ford F-150 pickup trucks from the 2011-2 model years are being investigated after the agency received 32 complaints — including two reports of accidents — about braking problems, according to the report, which noted one possibility was the failure of the electric brake vacuum assist pump.
“Brakes fail when vehicle is first started and either backing up or pulling forward,” one owner wrote in 2013. “Since this problem is serious in nature Ford should issue a recall before someone is seriously hurt or killed.”
In the fifth action, about 121,000 Dodge Darts from the 2013 model year are being investigated after the agency received complaints that the brake pedal “may be hard to depress suddenly and vehicle stopping distances may unexpectedly increase,” according to the report. There were 18 complaints, but no reports of accidents.
If the agency finds the concerns are valid, it will typically upgrade the investigation to an “engineering analysis,” a move that can lead to a recall.