If your Kia Sedona’s sliding door still won’t open (or if you’ve determined the problem is one you can’t fix alone), your best bet is to head to your local Kia dealership or mechanic for further help. Some fixes—like replacing a door seal or blown fuse—are inexpensive. But if you have to replace the sliding door motor, you could face a seriously steep bill: the average cost of replacing the power sliding door motor in a Kia Sedona is over $1,000.