501-09 Rear View Mirrors 2014 Fiesta
Description and Operation Procedure revision date: 04/29/2013

Rear View Mirrors - System Operation and Component Description

System Operation

Rear View Mirrors - Exterior, Power

The LH and RH exterior mirror glass movement is controlled by the exterior mirror control switch and the LH and RH exterior mirror motors. The exterior mirror control switch receives voltage at all times from the CJB . When the LH or RH mirror is selected using the exterior mirror selection switch, the selected mirror is adjusted when the exterior mirror control switch is pressed left, right, up or down. To control exterior mirror glass movement, the switch supplies voltage and ground to the appropriate exterior mirror motors.

Rear View Mirrors - Exterior, Heated

The rear window defrost switch controls operation of the heated exterior mirror glass. The heated exterior mirror glass only operates when the rear window defrost system is active. The heated exterior rear view mirror glass deactivates when the rear window defrost deactivates. The rear window defrost and heated mirrors self actuate when the ambient air temperature is less than 5°C (41°F) and engine coolant temperature is less than 65°C (149°F). The rear window defroster LED does not illuminate when the rear window defrost and heated exterior mirrors self-actuate. The heated mirror glass receives voltage from the rear window defrost relay located inside the BCM . The LH and RH heated mirror glass does not share the same ground.

Rear View Mirrors - Interior, Auto-Dimming

The interior auto-dimming mirror uses 2 integral photoelectric sensors to determine the exterior lighting conditions. When the forward facing sensor detects daytime conditions, the rearward facing sensor is inactive and the mirror glass stays in a high reflectance mode. When the forward facing sensor detects nighttime conditions, the rearward facing sensor is active. During nighttime conditions, the mirror stays in a high reflectance mode until bright lights (glare) are detected by the rearward facing sensor. When bright lights (glare) are detected by the rearward facing sensor, the mirror glass is electronically darkened in proportion to the brightness of the glare detected from the rear of the vehicle. To provide increased visibility when backing up, the interior rear view mirror automatically returns to a high reflectance mode whenever the transmission is in reverse, regardless of exterior lighting conditions.

Component Description

Exterior Mirror Control Switch

The exterior mirror control switch is a momentary contact switch that allows the driver to adjust the selected exterior mirror glass up, down, left or right. The exterior mirror selection switch is integral to the exterior mirror control switch and allows the driver to determine which exterior mirror will be adjusted.

Exterior Mirror

Each exterior mirror has 2 bi-directional motors that are used to control the up, down, left and right movement of the exterior mirror glass.

The heated exterior mirrors use heating elements that are integral to the exterior mirror glass.

The exterior mirrors may be equipped with turn signals. For more information regarding the turn signals,
Refer to: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

The exterior mirrors use a jumper harness between the vehicle wiring harness and the exterior mirror motors and the heated mirror glass. The exterior mirror jumper harness is integral to the exterior mirror. Before replacing an exterior mirror or motor, inspect the jumper harness for opens, shorted circuits or damaged and pushed-out pins. If a concern with the exterior mirror jumper harness exists, attempt to repair the jumper harness.

Interior Auto-Dimming Mirror

The auto-dimming rear view mirror has 2 photoelectric sensors, one on the front of the mirror (facing the windshield) and one on the rear of the mirror (at the top of the mirror glass). Based on inputs from these sensors, the mirror internally calculates and adjusts the reflectance level of the interior rear view mirror glass to eliminate unwanted glare. The reflectance level of the mirror glass is variable and depends on the amount of rear glare detected in relation to ambient light conditions in front of the interior mirror.