How do you change wire harness in door?

To change a wire harness in a door, first, disconnect the car battery to ensure safety. Remove the door panel by unscrewing any fasteners and carefully prying it off to access the wiring. Disconnect the old wire harness by unfastening any clips or connectors, then install the new harness by connecting it to the appropriate plugs and securing it in place. Finally, reassemble the door panel and reconnect the battery.