2006 chevy impala

My car will not come out of park. I have spoken with a dealer ship and they said it may be a wire loose on the shifter or the break pedal senser. Could you please give me so info. on how or what i need to do to check this out. Thanks

First make sure you have tried turning the steering wheel back and forth a little while turning the key

This system uses a brake pedal position sensor that feeds into the Body Control Module. The BCM activates the shift interlock solenoid. So press the brake pedal with the key in the ‘run’ postion but engine not running and listen for a ‘thump’ near the shifter. If you don’t hear the ‘thump’ there may be a problem with the pedal sensor or the solenoid.

BTW are there any other body functions that the BCM is not handling correctly?