A few things come to mind.
1 - steering angle sensor needs to be calibrated.
ELECTRONIC STABILITY PROGRAM (ESP)
If the vehicle is equipped with ESP, once the battery is reconnected, the Steering Angle Sensor (SAS) needs to be
calibrated. The SAS requires calibration anytime the battery or an ABS (ESP) component has been disconnected for
any length of time. To calibrate, perform the following:
1. Start the engine.
2. Center the steering wheel.
3. Turn the steering wheel all the way to the left until the internal stop in the steering gear is met, then turn the
wheel all the way to the right until the opposite internal stop in the steering gear is met.
4. Center the steering wheel.
5. Stop the engine.
2 - blown fuse. Check fuses 9, 17, and 21 in the front fuse block (under hood)
3 - dynamics sensor is disconnected. The dynamics sensor measures the yaw/rotation of the car and is located under the center console. This thread describes how to get to it and disable it, but you can refer to it for getting to it and making sure it's connected properly.