Some 1.4 million Toyota Motor Corp vehicles are being scrutinized more closely by U.S. safety regulators looking for possible increased fire risk, the National Highway Traffic Safety Administration said on Monday.
The expanded probe includes the manufacturer's best-selling Camry sedan from model years 2007 to 2009.
The probe was upgraded to an engineering analysis from a preliminary investigation, which may lead to an eventual recall. Often engineering analyses are closed without a recall.
Fires have been reported at a high rate for Toyota models built from September 2006 to August 2008 that all have the same power window master switch design, the NHTSA said on its website.
Nine injuries and 161 crashes or fires have been reported to either NHTSA or Toyota, but no deaths, NHTSA said. NHTSA reported there were another 49 warranty claims of fires or "thermal events" among the affected vehicles.
The expanded probe affects the 2007-2009 model year Camry, Camry Hybrid, RAV4 and Yaris vehicles, as well as 2008 Highlander Hybrid SUV.
In February, an investigation was opened by NHTSA into about 830,000 model year 2007 Camry and RAV4 vehicles. Monday's action expanded that to 1,424,747 vehicles, NHTSA said.
(Reporting by Bernie Woodall; Editing by Maureen Bavdek)