Its part of the self testing process the computer does. It does this so it knows whether sensors are operating properly. These tests are going on all the time while you drive your vehicle. It needs certain conditions to be met to complete. What these conditions are i cant say for sure. The drive cycle incomplete means its test didnt finish. You may just need to drive it more until you met these conditions. If it doesnt go away you may still have a problem. You could also try clearing the codes. You do this by disconnecting the battery cables. While holding them together count to 30. This should clear anything out of the computer. Anything that is still wrong will come back. I would save this for a last resort.