Your vehicle may have an automatic dimming rearview mirror with OnStar®, compass, and map lights. The compass automatically calibrates, or sets the driving direction, as the vehicle is driven. The automatic dimming feature enables the rearview mirror to sense nighttime glare from vehicle headlamps from behind and automatically dim to reduce the glare to a safe level. The automatic dimming feature turns on each time the vehicle is started.

Press the buttons located at the bottom of the mirror to turn the map lights on or off.

There are three additional buttons for the OnStar® system. See your dealer/retailer for more information on the system and how to subscribe to OnStar®. See OnStar® in the Index for more information.

The automatic dimming mirror function is turned on automatically each time the ignition is started. To operate the automatic dimming mirror, do the following:

1. Make sure the green indicator light, located to the left of the on/off button, is on. If it is not, press and hold the on/off button until the green light comes on.
2. Turn off the automatic dimming mirror function by pressing and holding the on/off button until the green indicator light turns off.

Press the on/off button to turn the compass on or off.

The direction the vehicle is facing appears on the mirror.

If a compass direction, (N for North for example) does not appear, there may be a strong magnetic field interfering with the compass. This can be caused by a magnetic antenna mount, note pad holder, or similar objects. If the word CAL appears in the compass window, the compass may need to be reset or calibrated.

To calibrate the compass, do the following:

1. Make sure CAL is displayed on the mirror. If not, press and hold the on/off button until CAL displays.
2. While CAL is displayed, drive the vehicle in circles at 5 mph (8 km/h) or less until a direction appears on the mirror.

Compass variance is the difference between earth's magnetic north and true geographic north. If the mirror is not adjusted for compass variance, the compass could give false readings.

The mirror is set in zone eight upon leaving the factory. The compass must be adjusted to compensate for compass variance if the vehicle is driven outside zone eight.

To adjust for compass variance, do the following:

1. Find your current location and variance zone number on the following zone map.



2. Press and hold the compass button until a Z and a zone number appears on the mirror.
3. Once the zone number appears on the mirror, press the compass button quickly until the correct zone number displays. If CAL appears in the compass window, the compass may need calibration. See "Compass Calibration" listed previously.

Cleaning the Mirror

While cleaning the mirror, use a paper towel or similar material dampened with glass cleaner. Do not spray glass cleaner directly on the mirror as that may cause the liquid cleaner to enter the mirror housing.