2008 Mercury Mountaineer Door Mirror Replacement Cost

A door mirror, also known as a side view mirror, allows the driver in a vehicle to observe the area on the side of the vehicle with a glance out of the window. Most vehicles, in fact all modern cars, trucks, and SUVs, have both left and right door mirrors. Some mirrors are manually adjusted; many are remotely adjusted with a switch inside the vehicle. The right side door mirror is often convex so that it provides a wide angle view. In some vehicles, the mirror adjustments are memorized by an electronic control unit (ECU) for customized settings. Door mirrors may also include auto-dimming, defrosting, and auto-adjusting capabilities.

A door mirror is adjusted so that the driver has a clear view of the side and rear of the vehicle and surrounding area. The door mirror does not show the area directly behind the vehicle, nor does it allow the driver to see a segment of the area on each side of the vehicle, the "blind spot". Each mirror should be adjusted so the driver has a clear picture of as much of the side and rear of the vehicle as possible. Together with the rear view mirror mounted on the windshield, the door mirrors should provide a viewing area in all but the two blind spots. For these areas, it is usually necessary for the driver to look over each shoulder. New technologies seek to eliminate the blind spots - as well as provide a view of the area directly behind the vehicle - through the use of video cameras and an onboard video screen.

Problems with a door mirror can fall into two general categories: mechanical and electrical. Mechanical problems might include a broken mirror glass or broken mirror housing. Electrical issues can range from a bad mirror adjustment motor to a faulty mirror switch, to a problem with an electronic control unit. Mirrors with auto-adjusting, auto-dimming, or defrosting capabilities may also develop problems with those functions.

Power door mirrors that have stopped adjusting or heating may still be manually adjusted to provide side view capabilities. In those cases, the vehicle may be safe to drive. If a mirror glass or housing is damaged or broken, however, side view ability will be limited. This presents a safety concern that should be taken care of as soon as possible by repairing or replacing the mirror.

The door mirror, whether manual or power operated, should last the lifetime of any car, truck, or SUV. But, because the mirrors protrude from the sides of the vehicle, they are prone to damage. It is not uncommon to have to replace a mirror or mirror housing for this reason.

If the problem with a door mirror is related not to damage caused from impact to the mirror or mirror housing, but rather to a fault in the system, a technician will use a multimeter to make sure that the mirror and the mirror switch are getting power. It may be necessary to check the individual circuits for each function in the mirror. In some cases, a technician will use a special scan tool to check the electronic control unit for proper operation.

If the mirror, mirror housing, or motor are found to be faulty and the mirror assembly needs to be replaced, the technician will remove the interior door trim panel (in most cases) to access the mirror wiring and the attachment fasteners. With the panel carefully removed, the technician will unplug the mirror's wire connector from the door wiring harness, remove the fasteners that secure the mirror, and remove the mirror from its mounting location. The new mirror is put in place, the fasteners attached, and the wire connector plugged in. The door trim panel is reinstalled and the mirror is tested for proper operation.

RepairPal recommends that, if a DIY door mirror replacement is to be considered, all of the mirror options (power, heat, etc.) be identical between the original mirror and the replacement mirror. This is especially important if the vehicle includes an electronic control module that will coordinate the mirror function.

It should be noted that many interior door trim panels are difficult to remove, and may contain one-time-use fasteners that need to be replaced when the trim panel is reinstalled. The wires and cables connected to the trim panel may be easily damaged. Some vehicles also incorporate airbags into the door panel. Care must be exercised when working around these airbag modules and wiring. Many door mirrors are color coordinated to the vehicle body paint. It may be necessary to have a new replacement mirror painted to match the rest of the vehicle prior to installation.

Many door mirrors can be replaced by someone with intermediate DIY experience. The interior door trim panel can be challenging to remove on some vehicles. Vehicle-specific repair procedures should be accessed to prevent damage to sensitive wires, clips, and cables on the inside of the trim panel.