When the battery is changed, a number of systems would have to be re-learned before they can operate correctly. Start by pulling up the car with the wheels facing straight and unhooking the cable of the negative battery contact. In the case of 2014 and older models, the steering wheel should be in its lowest position and pushed out to the utmost length and turning the wheel counter clockwise about 90 degrees. Find the opening, insert a small flat-bladed screwdriver in the opening and twist the screwdriver to the left to loosen the retainer. Turn the steering wheel 180 clockwise then repeat the steps to unlock the left side retainer by turning the steering wheel 180 clockwise and then proceed to carefully remove the airbag module off the steering wheel and disconnect the electrical connectors and then remove the airbag. With 2015 and subsequent models, turn the steering wheel 90 degrees off-center, counterclockwise and insert a 5 or 6 mm Allen wrench or punch into the access hole and press the tool parallel to the steering column and slightly lifting to release the internal spring. You will have to repeat the process in 180 degrees then you will have to very carefully peel off the airbag lying in the steering wheel as a way of disconnecting the electrical connectors and removing it. In the event that steering wheel has never been removed, there might be a layer of plastic over the tool access hole. Place the module in a safe place with the airbag side upwards. Then, take out the steering wheel bolt with a 12 mm, 12-point spline-drive bit, and note the steering wheel location with regard to the steering shaft in the event there are no alignment marks. Unscrew the steering wheel off the shaft, observing how any electrical wire harnesses are routed and, where necessary, tap it towards the middle or twist it as one pulls it up. Apply a bit of tape over the clock-spring to ensure that it does not turn. To install, screw the wheel onto the steering shaft, aligning the index marks and connecting any wiring harnesses and screw a new steering wheel bolt and tighten it to the appropriate torque. Install the electrical contacts of the horn and airbag module and attach the airbag module to the steering wheel and fix it.