Circuit Operation

The Electrochromic Mirror uses two photocell sensors to determine light conditions in the front and back of the vehicle. At night, as the glare of headlamps from behind increases, the mirror gradually becomes darker to absorb the glare. In the daytime, the mirror is in a clear state. With the ignition switch in "RUN," battery voltage is applied to mirror connector terminal 1. With the gear selector lever in reverse, battery voltage is applied to terminal 3. The mirror will gradually change to a clear state.

With option DD0 (automatic outside mirror), the interior mirror also controls the reflectivity of the LH Outside Mirror. The LH Outside Mirror darkens or clears along with the interior mirror.

An electronic compass is contained within the Electrochromic Mirror. The compass display is located on the mirror. It presents directional displays relative to symbolic horizon lines and road lines.

The electronic compass includes a fluxgate magnetic field sensor and a microprocessor. The microprocessor receives inputs from the sensor, processes them and provides outputs to the compass display which indicates the vehicle heading, relative to the Earth's magnetic fields.

Compass Variation Zones (Part 1 Of 2):

Compass Variation Zones (Part 2 Of 2):

Setting the Electrochromic Mirror Compass to the proper zone.
First determine the correct zone location. Display the current compass zone setting by inserting the end of a paper clip into the hole on the bottom of the mirror and pressing the calibration switch. Press and hold the switch for 5 seconds or until a zone number appears in the display. To change the current zone setting press and hold the calibration switch, until the correct zone appears, release the switch and a compass direction will be displayed within a few seconds. The zone setting will not be lost when the mirror or ignition switch is turned "OFF." The zone requires resetting only when the vehicle is outside of the zone for which it is set.

Calibrating the Electrochromic Mirror Compass using the "Autocal" feature.
The Electrochromic Mirror has an "autocal" compass and will automatically calibrate itself, so that each vehicle's unique magnetic fields do not cause the mirror to display the wrong compass direction. This calibration happens during normal driving conditions. When the compass is calibrating a "C" will be displayed, calibration is complete when the "C" in the display changes to the correct directional heading. Once the mirror is calibrated it will not need to be recalibrated. The calibration will not be lost when the mirror or ignition switch is turned "OFF."

Calibrating the Electrochromic Mirror Compass manually.
1. If the "C" is being displayed, drive the vehicle slowly (5 mph or less) in a 360 degree circle until the display reads a compass direction.
2. If the "C" is not being displayed turn the ignition switch "ON" and the Electrochromic Mirror "ON." Press the calibration switch by inserting the end of a paper clip into the hole on the bottom of the mirror and hold for 10 seconds until the letter "C" appears in the display. Now drive the vehicle slowly (5 mph or less) in a 360 degree circle until the display reads a compass direction.