[DG] [DG11] ST7002 Autopilot

[Phmacneil]

Good morning from Green Turtle Cay, Abacos. I’m hoping y’all can help me solve my autopilot (Raymarine ST7002) problem. We recently crossed from Ft. Pierce to the Abacos and the autopilot worked fine until we made the banks. The ap began to drift off course 30 degrees to starboard. The +1, -1, +10, -10 buttons would show desired heading changes correctly on the ap display pad at the helm without any corresponding changes to the rudder or actual course being steered.

I checked the locker areas near the fluxgate compass in the aft stateroom and found no metal objects that may have interfered with the compass.

I recalibrated the autopilot compass by turning the boat in circles and found only a 2degree variation. I completed the recal and the compass at the helm agrees with the autopilot control/display pad and the MFD( off by 1degree).
The rudder indicator on the ap display shows correct positions of the rudder.

While sitting still with the ap display showing a heading straight ahead, I turned the rudder full starboard and touched “auto” and the ap turned the rudder back to center to the straight heading. The same was confirmed when turning to port.

The + and - degree buttons still would not change the rudder angle.

I finally completed a system “reset” and while doing so noticed the Latitude was still set at 38 degrees; the same as when commissioned in 2008. (I mistakenly thought the MFD would provide the current Latitude to update the ap Latitude setting. )
I changed the Latitude to 26 degrees and completed the reset. Unfortunately, the + and - degree buttons will still not change the rudder heading.

I searched the Raymarine forum, but did not find a similar discussion of the symptoms.

Any ideas and suggestions are most welcome.

One last bit of info, I checked the source for the autopilot on my eS127 MFD and it shows 2 sources; STNG and NMEA. The NMEA is selected. I tried to select STNG but it will not allow it to be selected and switches back to NMEA.

Also, if we need a raymarine technician, is there anyone in the Bahamas? We are currently in the Abacos.

[Derek - Raymarine - Moderator]

Hi Phmacneil

Thank you for your enquiry,

I have attached an FAQ detailing some fault analysis please click here which will go though checking the drive itself, its clutch and motor, the rudder reference unit and the output from the course computer to the drive.

The latitude setting will make no real difference to the general operation of the autopilot, it will reduce the amount of rudder applied on Northerly headings but you should still get a good response to the course change commands input by the control unit.

The source selection in the MFD is again not really relevant to the general operation of the autopilot, you should still have full control of the Autopilot from the control unit.

Your description indicates the rudder feedback unit is working correctly, you indicate the heading works correctly, (a simple test is to turn the wheel by hand and the rudder angle should follow the wheel and the compass heading should regularly and evenly swing through 360 degrees as the boat is slowly motored in a circle.

Selecting AUTO should result in the wheel appearing to be 'locked' as the clutch engages and the test described in the FAQ will indicate that the drive itself operates fine.

In which case, the computer must be at fault.

I am afraid we do not have a recognised Raymarine agent in the Bahamas that I am aware of.
Thanks
Derek