TMQ AP4 - Compass Calibration

TMQ AP4 Autopilot (AP4S10) 48 of 62 Version 4.96 9/10/2017
Compass Calibration
The compass supplied with your AP4 autopilot has been calibrated during
manufacture. This calibration will be satisfactory for almost all installations. If
you have a steel vessel, or some other factor which causes the compass to
perform poorly, the calibration procedure will adjust compass characteristics to
compensate. The calibration should only be done if the compass is known to
be inaccurate.
If the AP4 compass displays a constant offset (eg the autopilot compass reads 3
degrees high on all bearings), simply rotate the AP4 compass case to align
bearings with the ships compass. In this case it is not necessary to re-calibrate
the compass as described below.
If the AP4 compass has inconsistent variation on different headings, the
following calibration procedure can be carried out. This procedure should only
be done in calm waters with adequate sea room.
Calibrating TMQ Compass - COMMAG
 Rotate MODE switch on AP4 to SET
 Press and hold pressed the GPS button
 Press TIMER button – display should read 900
 Release GPS and TIMER buttons
 Rotate COURSE knob until display reads 901
 Press TIMER button
 Display should flash between CAL and current boat heading
 Turn the boat slowly through two complete circles in the same direction
 On completion of turns press and hold pressed GPS button
 Press TIMER button
 Release both buttons
 Rotate COURSE knob until display reads 902
 Press TIMER button
 Display should revert to read normal boat heading
Note: If the autopilot does two (2) beeps, the calibration was invalid and the
AP4 defaults to the factory setting. Repeat steps above to carry out
calibration again. This will occur if vessel does not complete the circles.