2002 Montero Sport Sputtering Problem

I have a 3.0 L 2002 Montero Sport LS with 74K miles. I recently got my SUV back from the body shop and while idling I turned off my AC where the car preceded to sputter and die. When I got home I tested the car by turning off the AC while idling. The car did not die, but the RPMs did dip a bit while the car sputtered, only to go back to normal. A couple of times while at stop lights the check engine, oil, and battery lights came on, almost as if I had the battery on and nothing else. The RPMs did dip, but the car did not die. I talked to a couple people and they say it could be the battery. Any ideas?

Other than this, the car hasn't had to be taken to the shop at all.