The magnetic compass not showing the correct heading can have several causes:
1. The compass is not properly calibrated. See here how to calibrate the compass.
2. Surrounding metal structures can cause deviation of Earth’s magnetic field, this is especially prevalent indoors. Go outside to an open area clear from metal structures to calibrate and test the compass again.
3. Placing MAX close to other electric devices or electrical circuits, MAX can experience electromagnetic interference. Position MAX away from sources of electromagnetic interference.
4. Depending on your geographical location declination of the Earth’s magnetic field can cause the magnetic North to deviate from the geographical North (as displayed by GPS heading) by up to 20+ degrees. Deviations up to 5-7 degrees are quite common.
Because of it’s higher accuracy and faster update rate we advice to use GPS heading (COG) instead of magnetic heading whenever possible. The boat needs to be traveling to calculate COG, if the boat is stationary COG will display the magnetic heading instead.
If you continue to have problems, please contact our Customer Support.