The recall covers Dodge Grand Caravan and Chrysler Town and Country minivans from 2008 to 2010 model years and Dodge Journey SUVs from 2009 to 2010.
The automaker is advising customers to remove all items from their key rings, leaving only the ignition key, until the switches can be fixed. If there is a key fob, it should also be removed, Fiat Chrysler said in documents posted by the National Highway Traffic Safety Administration.
The company said road conditions or a jarring event may cause the ignition switch to move into the off or accessory position, turning off the engine and disabling the air bags, power steering and power brakes.
Fiat Chrysler said it expects to begin replacing the defective ignition switches for the 2008-2009 minivans and SUVs in April and the 2010 vehicles in August.
Some of the vehicles had previously been recalled for the same issue.
General Motors experienced a similar ignition switch problem and recalled 2.6 million small cars last year. At least 57 people were killed and more than 90 injured in crashes linked to the defective GM switches.