Autopilot looses calibration?

[wmcunninghamii]

I have the ACU 200, EV1 sensor and type 1 linear drive installed on my 30 foot 7500 pound sailboat.

I completed a sail from California to Hawaii with very good performance of the autopilot although performance mode does not like large following seas. When I changed mode to cruising the pilot held course reasonably well in 8 to 10 foot following seas, 25 to 30 Kts wind.

About 2 days out of Hawaii on the return trip the AP was engaged but went hard over to starboard. I rebooted the ACU 200 and control head (they are on separate breakers) several times with no help. I then powered on and switched to my ACU 100 wheelpilot (backup system). The ACU 200 was powered down and was not used for the remainder of the trip.

Upon reaching port on the Mainland I decided to rerun the dockside wizard with the ACU 200 again powered up and interfaced to the system. The ACU 100 was, of course, powered down. I was able to successfully run the dockside wizard, performed the rudder cal successfully and all was good. However, after operating well for several weeks the system once again went hard over and once again I had to re-perform the rudder cal to get the system back. I am also seeing intermittent instances of the ACU not being detected when first powering on the system. I can usually get it back by resetting both instruments and ACU repeatedly but it is certainly flaky.

The fact that the ACU 100 wheel pilot operates successfully when interfaced with the EV1 and never fails to be detected leads me to believe there is something odd going on with the ACU 200.

Can you please provide advice an further troubleshooting?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum wmcunninghamii,

It is recommended that you identify the versions of software which are installed within the ACU-200, EV-1 Sensor Core, and p70/p70R Autopilot Control Head. This information may be obtained via the autopilot control head (MENU->SET-UP->DIAGNOSTICS->ABOUT SYSTEM). Should any of the autopilot components not be operating with the latest available Raymarine product software update, then it would be recommended that the update(s) be performed. Updating the Evolution Autopilot's software will necessitate that a Pilot Factory Reset (MENU->SET-UP->AUTOPILOT CALIBRATION->COMMISSIONING->PILOT FACTORY RESET) be performed, followed by the Dockside Wizard. The Evolution software update and subsequent Pilot Factory Reset will cause deviation data stored within the autopilot to be deleted, necessitating that the autopilot once again create its deviation table and report the maximum detected deviation.

If updating the autopilot's software, it is recommended that the ACU-100's software be updated as well should it not presently have the latest software installed.

Should the problem persist thereafter, then it would be recommended that the ACU-200 be sent to Raymarine’s Product Repair Center to be bench checked / serviced.

[wmcunninghamii]

OK, I will check software, perform updates if/as required and report back.

[Chuck - Raymarine - Moderator]

You're welcome.

[wmcunninghamii]

OK, I finally had an opportunity to review and address SW versions. I found almost all of my gear was out of date, i70P, ACU (both 100 and 200) , the CCU, an i70 instrument and an i70s which I just purchased.

Whew, that all took about two hours to get updated. The good news is my preliminary checkout was good with the ACU 200. I still need to re-do the post software update re-calibration but so far so good.

The concern I have is why would a stable system with no equipment modification suddenly become unstable with the fix being software updates? This seems odd to me. Does this imply the software somehow becomes corrupted, has Raymarine seen corrupted software issues in their systems? It would be helpful to know this for future reference.

[Chuck - Raymarine - Moderator]

wmcunninghamii,

As the design of the Evolution autopilots is heavily dependent upon speed data from the system, early Evolution autopilot software would perform may perform well until a problem was encountered with the installed speed through water sensor. Later software included improvements ... even one to select use of SOG over Speed (through water) for autopilot calculations.

[wmcunninghamii]

Chuck,

The bad news is the ACU failed to connect once again after operating well with new software for a short time.

The good news is I have isolated the root cause and have repaired it.

My concern with just sending the unit back for warranty was the intermittent nature of the problem. I had a splice in the ACU 200 STNG cable in order to lengthen it and, as a Hail Mary, I decided to take a closer look at that splice. Physically it looked fine, no pull apart, all wires sealed and no physical indication there was any weakness. However when I removed it an ohmed it out I found an open on the CANL (white) wire. Apparently the system will sometimes work when CANL is open. It may have been intermittent but looked like a hard failure to me.

In any event, I repaired the splice and reinstalled. All is good. This time I soldered and shrink wrapped all the wires, no more butt connectors for me.

[Chuck - Raymarine - Moderator]

wmcunninghamii,

Thanks for the update. Glad to learn of your success. For the benefit of others diagnosing equipment issues, cable splices are among the most common and overlooked causes of system communications failures. When seeking assistance with a system problem, please be certain to check any splices and to notify the Raymarine's Support Team of any splices within communications and/or transducer cables.