With most late model cars, the outside rear view mirrors attach to the outside door frame with three bolts, located under the plastic shroud located inside the door, directly opposite the mirror. Since the automotive industry moved away from glass mirrors with metal hand adjusted mirrors to reflective plastic mirrors housed inside of a plastic shell, this has been the standard for most models. Due to the level of high abuse that these mirrors can take, they remain in use because they rarely break on impact.
Remove the mirror shroud from the inside of the door frame. The shroud usually press fits onto the door with little plastic tabs. Remove it by pulling on it to release the tabs. In some cases, screws hold the shroud in place. If this is the case, remove the screws with a screwdriver before pulling the shroud off the door.2
Disconnect the wiring harness for the electronic controls located inside of the mirror. Not all mirrors have electronic controls. If you do not see a wiring harness behind the shroud, skip this step.3
Remove the nuts that secure the mirror to the door. Usually, there are three threaded posts molded into the plastic cover of the mirror. Use a long-well socket and ratchet to make it easier to reach the nuts. As you remove the last nut, the mirror wants to fall out of the door. Hold it, or have someone hold it so it doesn't fall and scratch your paint when you remove the final nut.4
Inspect the new mirror to ensure the base (the part that presses against the door) has a rubber seal on it to prevent water from getting into the door. If it does, move to the next step. If the seal is missing, transfer the seal from the old mirror to the new one.5
Slide the threaded posts into the door and secure them with the nuts supplied with the new mirror.6
Reconnect the wiring harness. If the mirror does not have a wiring harness, skip this step.7
Press the shroud into place to hide the wiring harness and nuts.