The problem happens in less than three-hundredths of a percent of the vehicles on the road, Mayne said.
NHTSA began investigating the air bags in October of last year after getting complaints about air bags inflating for no reason in Jeep Libertys. Investigators traced the cause to electrical stress on one of two circuits in the control computer. The problem also causes the seat belts to tighten as if a collision were about to happen.
The Grand Cherokees covered by the recall were built from Aug. 1, 2001 to May 16, 2003, while the Libertys were built from June 6, 2001 to March 19, 2003.