[DG] [DG11] Autopilot Drops into Standby and other issues

[[email protected]]

Hi There-
We're using an ST6001+ autopilot head and course computer for same (not sure of model, but 2002 era).

This system is also networked via STng to 2 MFDs (A65 and E98), radar, AIS, STng bus, converter, Tridata, Wind instrument, etc.

Issues:
1) Phantom “Next Waypoint” prompts when there is none in the system, and we’re not even on a route, simply a Go To cursor, for example.

2) Unit drops from Auto into Standby, typically with no alert and no warning, of course. Sometimes it will beep. This is most often when autopilot is in a very low-strain situation. Sometimes (but not often) in a heavy seaway.

I have already re-done every electrical connection at main course computer (gray box), and confirmed voltage is not an issue (we run lithium batteries, voltage almost never lower than 13.1). It often will do this on flat water, motoring with 13.5+ volts in the system.

[Derek - Raymarine - Moderator]

Hi Randy,
Thank you for your enquiry.

The dropping to STANDBY symptom is either caused by voltage brownouts - spikes in the power supply or temperature related where the course computer is running hot.

Please check out this FAQ related to Electrical noise and also look at this FAQ regarding constant activity of the drive

You indicate that your batteries are good and you have checked the connections to the computer and the drive, you should not see a voltage drop of more than 0.5 volt when the drive is actually operating under heavy load.

Possibly the drive motor is taking a heavy load, possibly stiff steering or a mechanical issue with the drive?

The issue could also be related to frequency of operation, if the drive is constantly hunting to and fro, the frequent motor reversals will drive current up as well as generate excessive heat in the motor and in the course computer, if the drive FETs in the course computer get too hot they will trigger the computer to shut down. It is also possible there is a fault with the drive FETs inside the course computer and they are breaking down prematurely in which case the computer should be returned to the service workshop.

Regards

Derek

[[email protected]]

Hi Derek-
Thanks for your reply. As mentioned in my initial post, these issues often present themselves when the autopilot is actually very lightly loaded, sometimes while motoring long distances on flat water, so certainly not an overloaded situation, my any measure. In these cases, where would your troubleshooting take you? Straight to a fault with the course computer unit itself?

[[email protected]]

Also, I don't see anything in your reply related to the phantom "next waypoint" messages we get from time to time. Any ideas on that?

[Derek - Raymarine - Moderator]

Hi Randy,

With regards to the dropping to Standby issue first, if the drive is not constantly reversing to and fro - which you will only detect by listening to the drive motor itself, then the next area I would check is the steering system itself - is there something that is making the drive work hard even if the sea state is slight? Touch the motor, is it hot - greater than 50 degrees C? ( this is just about the max temp you can keep your hand on) - if yes, either the drive motor is faulty or the steering is very stiff.
If the drive is cool, then the computer is the likely culprit.

With regards to a phantom waypoint - is there a symbol next to it? for example an N or an S?

If N - this is a waypoint generated somewhere through NMEA and being circulated into the network. If S - it is likely caused by a data loop and this is a SeaTalk waypoint, possible there is a date loop with SeaTalk and NMEA and due to the data delays in translation, although you might cancel it - it will reappear again.

You need to identify the NMEA source or the cause of the data loop.
Thanks
Derek

[[email protected]]

Hi Derek-
No indication of extra work or heat generated by the drive unit. So I guess we should suspect the course computer then. Dang.

I should have been more clear on the phantom waypoint. This is on the Autopilot ST 6001+ head unit only. I don't think anything at all shows up on the chartplotters. Never recall seeing any letter associated with the display, just "next waypoint?" which we typically just press auto to remove it.

[Derek - Raymarine - Moderator]

Hi Randy,

OK, sounds like the computer needs to be removed to a service dealer to check out.

With regards to the phantom waypoint, there must be something connected to the NMEA of the course computer or to the NMEA input to the control unit which is triggering this waypoint advance, NEXT WAYPOINT typically means the autopilot thinks it has reached the alarm zone around the target waypoint and is identifying that to you.

It could also be tied up to the issues with the course computer, so I would check the NMEA connections and then get the computer sent back.
regards

Derek

[[email protected]]

Hi Derek-
Thanks for your help on the troubleshooting. Unfortunately I have no idea when we might be able to send the course computer unit in for service, as we're cruising full-time, and currently in Mexico hiding from Coronavirus. It might be a LOOOOooooNG time before we can do anything with it.

I'm confident that the issue is not because of a connection error, as nothing has been changed. I can also say with confidence that this issue never showed up before the installation of our two chartplotters and STng backbone in Nov 2015. The course computer is not connected directly to the backbone, but only through to the Autopilot head unit, as before. Might this be the root of the issue (just thinking this through right now, actually)?

If you have any other suggestions for things we can try on our own, I think it's best to assume we won't have any professional help for quite some time.

Also, do you have any service centers in Pacific Coastal Mexico?

[Derek - Raymarine - Moderator]

Hi Randy,

Thanks for the feedback, our website is the best way to find local support, we have agents near Cuidad del Carmen or further north near heroica vera cruz, or on the eeast coast near Puerto vallarta or acapulco, otherwise, there are no other dealers there.

I would try a couple of things, temporarily isolate the pilot from the rest of the network, does the drop out issue still happen? (Isolating you should lose the phantom waypoint too)

If the dropout still happens, temporarily run two thicker cables direct from the batteries to the ACU, does the drop out still happen? Check in the calibration of the pilot, get into the drive settings and increase damping to the maximum of 9, does the problem still happen?

Thanks
Derek

[AnOd]

I had a similar problem with my autopilot going in to standby without any warning. I found out that it was the heading info that dropped out because I by misstake had powered the network from two different sources. When I let the autopilot be the only source of power everything went back to normal

/Anders