The KIA Optima uses a 12 volt charging system with an alternating generator and a frame-grounded starting battery. The alternator is a smaller unit with an internal voltage regulator. The bushings, windings and regulator may wear out and fail, requiring replacement. The average backyard mechanic can change the alternator in a KIA in about an hour.
Disconnect the battery's positive terminal bolt by turning it counterclockwise. Set it away from the terminal.
Jack up the Optima and remove the front passenger side wheel by turning the lug nuts counterclockwise using the lug wrench. Set the wheel and tire aside.
Remove or fold aside the wheel well cover by turning the small screws counterclockwise and gently pulling it from the retainer clips. This will give access to the engine.
Push on the belt tension pulley until the belt loosens, then pull the belt off of the alternator's pulley wheel. The belt can be left hanging in place.
Turn the alternator's bolts in a counterclockwise direction using the socket wrench. A smaller wrench head may be required for the tight space.
Pull the alternator free by wiggling it out of the mount.
Position the new alternator into the mount and secure the bolts that hold it in place.
Push on the belt tension pulley to give enough slack to wrap the belt around the alternator's pulley wheel.
Restore the wheel well cover by pushing it onto the clips and securing the screws.
Replace the wheel by tightening the lug nuts in a clockwise direction, alternating the pressure of opposing bolts. This sets the wheel better than tightening all of the nuts in a circle.
Lower the Optima onto the ground, and reconnect the battery.
