Compass Accuracy
Driving near power lines, or driving in the area of large iron or steel structures can temporarily change the compass heading. If the compass remains inaccurate after driving near such objects, calibrate the compass. Refer to Compass Calibration .
Most geographic areas (zones) have a magnetic north compass point that varies slightly from the northerly direction on maps. This variation is 4 degrees between the adjacent zones and becomes noticeable as the vehicle crosses multiple zones. A correct zone setting eliminates the error. Refer to Compass Zone Adjustment .
Special Tools Illustration Tool Name Tool Number Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool
Scheme 32
Vehicle Demagnetizing
| CAUTION | During demagnetizing, the demagnetizer coil pulls toward the vehicle. Place a cloth over the vehicle roof to protect the vehicle surface if contact occurs. Make sure the cloth covers the front third and the entire width of the roof. |
Note. The demagnetizing process requires the use of a demagnetizing coil commonly used by television repair technicians to demagnetize television tubes.
Note. To demagnetize, use a constant circular motion over the vehicle roof. Do not turn off the demagnetizer while sweeping the vehicle roof to prevent remagnetizing ferrous materials contained in the vehicle.
Note. During the demagnetizing process, make sure the phenolic surface of the tool (the side opposite the handle) is closest to the vehicle surface.
- Demagnetize the front third of the vehicle roof. Turn on the demagnetizer at least 1 m (3 ft) away from the vehicle. Holding the demagnetizer no more than 2.5 cm (1 in) from the vehicle roof and starting on the passenger side, demagnetize the front third of the vehicle roof closest to the windshield using a constant circular motion. Keep the circle radius within 30 cm (12 in) while sweeping across the entire surface of the vehicle roof closest to the windshield. Continue the circular motion 4 times. After the fourth pass and without stopping, move the demagnetizer at least 1 m (3 ft) away from the vehicle. Turn the demagnetizer off.
- Carry out the compass zone adjustment procedure. For additional information, refer to «Compass Zone Adjustment»(ref-292255-S28847125862008073100000) .
- Carry out the compass calibration adjustment procedure. For additional information, refer to «Compass Calibration»(ref-292255-S38234410752008073100000) .