2004 Pontiac Bonneville Owner's Manual - Page 192
2004 Pontiac Bonneville Manual
Page 192 highlights
Calibrating the Compass All electronic compasses need to know the magnetic profile of your vehicle. This is called calibration and is done automatically by your compass. However, if you would like to manually calibrate the compass, the following instructions will show you how. Sometimes, strong magnetic fields can affect the compass. If the compass display does not show a direction, and CALIBRATE COMPASS is displayed on the DIC, try calibrating the compass as follows: 1. Drive the vehicle to an open, flat area. 2. Press MODE to display COMPASS CALIBRATION. 3. Press SELECT to display PRESS RESET TO RECALIBRATE and then press the RESET button. 4. The display will change to SLOWLY DRIVE IN SMALL CIRCLES. Drive the vehicle in small circles. Do not drive faster than 10 mph (16 km/h). 5. Continue to drive in circles until the CALIBRATION COMPLETE message is displayed on the DIC and a direction is shown for the compass. Your compass should be calibrated. You will know this when a direction is shown and the CALIBRATE COMPASS message is no longer displayed. Compass Accuracy Your compass may show different headings around bridges, power lines, large metal objects and steep hills. This is normal and is true of compasses in general. If you put large metal objects like golf clubs in the trunk they could affect accuracy. If the affect is minimal, the compass will adapt to these objects over time. If you use an antenna with a magnetic base, it is best to mount it away from the center of the trunk near the rear window. The rear defog system can affect accuracy, and the compass corrects for the rear defog. However, if the rear defog is turned on while making sharp turns, the accuracy may be off. When you turn the rear defog off again, the accuracy returns to normal. Be aware that metal objects are sometimes buried in the ground. They can affect accuracy and you may not know they are there. As an example, many concrete roads have metal reinforcements inside. Also, if you drive with the trunk open, this could affect accuracy and could decalibrate the compass. 3-72