million vehicles worldwide sold under the Toyota and Scion brands.
This is the largest safety-related service action the maker has announced since it began a series of recalls related to the risk of unintended acceleration in late 2009.
That and other safety issues led Toyota to recall 14 million vehicles in 2009 and 2010. It's the biggest single recall since Ford Motor Co pulled back 7.9 million vehicles in 1996.
Many of the vehicles involved in the new Toyota recall also were called back one or more times due to unintended acceleration issues.
The latest recall is the result of a problem with a potentially defective power window switch on the driver's side of the affected vehicles which, the maker says, "may experience a 'notchy' or sticky feel during operation.
Toyota already announced recalls for several models involving similar window switches and in February, the National Highway Traffic Safety Administration announced it would open an investigation into the issue.
But at the time it focused on just 830,000 Camry and RAV-4 models sold during the 2007 model year.
One can check one's call on the Toyota's recall web page.
The maker estimates the inspection and repair process will take little more than an hour and involves the dis-assembly of the master switch and, if necessary, the application of a special fluorine grease.
NHTSA has received more than 200 reports of problems involving the defective switch including fires, though there are no known crashes or injuries.
At least 39 similar problems were reported in Japan, where 460,000 Toyota vehicles were recalled.
Another 1.39 million vehicles are subject to the new recall in Europe, while the massive safety campaign also covers Australia, China and other parts of Asia and the Mideast.