Ag Leader GeoSteer Operation Manual - Manual (Page 69)

Auto Calibrate
Operator’s Manual 55
Compass Calibration
The GeoSteer Control Unit has a built in compass that allows it to determine the heading the vehicle is facing. The compass
needs to be calibrated against the heading calculated by the GPS system. For this step the operator must drive the vehicle in a
slow circle to allow the GeoSteer to compare compass readings with the GPS heading.
To successfully calibrate the compass, start driving the vehicle 0.5 to 2 mph (0.8 to 3.2 k/h). Turn the steering wheel and hold
it at a constant angle so the vehicle will make a constant radius circle. Steer the vehicle so it makes a circle around 30 to 50 feet
(9.1 to 15.2 m) in diameter. When the vehicle is moving at the correct speed and in a circle, press the Start button to start the
calibration. Continue driving in a circle until the compass calibrates and the Waiting for Heading screen appears.
Note: In order to increase the integrity of the Compass Calibration, the driver must hold the steering wheel at a constant angle
and keep the vehicle at a constant speed. Do not start the calibration process until the vehicle is in this constant arc.
Note: Pressing the Pause button and then pressing the Resume button will restart the Compass Calibration from the
beginning. Do not press the Pause button unless the vehicle is going to cause an accident.
Figure 2-52 Compass Calibration
When the Compass Calibration step has completed, the system will automatically move to the next step.
Wait For Heading
After the compass has been calibrated, the system will display a verification screen. This screen shows a compass with a red
needle and a green shaded area. The red needle represents the calculated heading based on the GPS. The green shaded area
represents the compass heading. If the calibration was successful, the needle and shaded area should be pointing the same
direction.