Autopilot Disengages Intermittently for No Apparent Reason

[CampDavid]

I have a Raymarine below deck auto pilot, linear drive (SG1), St6000 control head on my Beneteau 4oo.

It works flawless with one exception, from time to time it will disengage, it is for no aapparent reason. It can go for hours and then go to standby with no notice and for no reason.You never know when or why.

I have checked the terminals at each connection point, asked raymarine for advice and remain after a number of years at a loss.

I feel that I need to find the problem however I am never sure if I get anywhere as the system works fine 95+ % of the time and always reengages with the push of the auto button.

Prior to shipping things off to Raymarine and spending big money perhaps somebody out there might have a few suggestions that I can follow in a quest to find the gremlin.

Thanks a Million

Fletch

[cwetto]

i have the same combination, except drive is "unknown" for me. Purchased with the new boat 2004.
The same problem with disengagement Last year twice, this year once.
Local Raymarine shop in Turkey try to fix it, but without succes. We cant reproduce the gremlin
Try to become a friend with gremlin, feed him once or twice a week and this will be happy living together ...

[Vasco]

Voltage problem?

[DeepFrz]

It works flawless with one exception, from time to time it will disengage, it is for no aapparent reason.

Is this an oxymoron? How can it possibly work flawlessly if it fails in a way that could kill you?

Were you transmitting on a radio at the time of disconnect? If so it could be RF related.

Be careful, I know of at least one boat lost because of this problem.

[AnchorageGuy]

Fletch, This is a common problem with the Raymarine autopilots and 99% of the time it is a voltage problem. You need to check batteries first and then EVERY connection on the autopilot. Do not over look the ground connections since they are often the culprit. Chuck

[S/V Alchemy]

If it's a voltage drop problem and not corrosion-related, sizing up the power leads to a heavier gauge would likely help and/or shortening the distance to the power terminal strip or however you have it rigged.

It's amazing the loss you can get with a smaller gauge lead.

[John A]

I would suspect the wiring from the control unit to the autopilots computer. Reattach the wires in the mickey mouse clamp on the computer. If that dosen't correct the problem, consider changing those three wires as corrosion can occur inside of the insulation of small gauge wires.

[Noname]

I had the same problem. My wheel pilot plugged into a 12v plug in the cockpit and on infrequent occasions the plug would lose continuity momentarily, essentially shutting down the autopilot, but the plug would regain continuity but the control head would be automatically on standby. Cleaning up the plug connection stopped the poor connectivity problem for me.

[lrclough]

I have similar problems on the Raymarine below decks Smart Pilot S-2 controller with the T-2 hydraulic drive. I reconnected everything but the autopilot still seems to disconnect and then will not reconnect for 1-2 hours.

Raymarine tech support recommends a new solenoid, which of course is currently out of stock. I am getting the correct ohm reading on the solenoid.

Tech Support did initially suspect the voltage supply to the unit as the primary source of problems. The connectors within the controller are too flimsy for a heavier grade of wire.

There are no diagrams that I can find with respect to the system.

[donradcliffe]

Originally Posted by lrclough

I have similar problems on the Raymarine below decks Smart Pilot S-2 controller with the T-2 hydraulic drive. I reconnected everything but the autopilot still seems to disconnect and then will not reconnect for 1-2 hours.

Raymarine tech support recommends a new solenoid, which of course is currently out of stock. I am getting the correct ohm reading on the solenoid.

Tech Support did initially suspect the voltage supply to the unit as the primary source of problems. The connectors within the controller are too flimsy for a heavier grade of wire.

There are no diagrams that I can find with respect to the system.

There seems to be a batch of marginal solenoids out there. If the solenoid is stuck, tapping on it will sometimes help.

When the autopilot loses control, do you hear the drive motor running? Can you turn the wheel, or is it locked? What does the display say? What is the voltage going out to the solenoid?

What happens when you try to reconnect?

[lrclough]

The Raymarine autopilot replacement solenoid is now back in stock after being out of stock for some time. The hydraulic tech on St Martin says he sees a lot of bad solenoids.

The part comes with a superfluous housing, inside of which is the solenoid proper that fits inside of the housing built into the hydraulic ram proper.