Autohelm ST 4000 Problems

[Don]

I have been following other posts on this subject and require some clarification.My Autohelm originally drifted off to port gradually and I assumed it was some sort of slippage and cleaned everything thouroughly which did not fix it.After a partial winters rest it now turns hard to port as soon as it is engaged so I think I may be making progress. Other posts talked about the contacts and replacing parts on the control head. I will attempt to remove and take a closer look at it this weekend but would appreciate any additional info on exactly what I should be looking for . Thanks Don

 

[JC on Bainbridge]

That happened to us about 10 years ago

It was working fine, and in the midst of a 2 week cruise, it started to do 360s. No matter what I did to it, it just wanted to do 360s. I took the unit's control head to the Autohelm dealer/service center, they repaired it, and it has been working fine since then.If you don't have anything cloe to your fluxgate compass, or have not made any changes to your boat between the time when it worked, and when it started to go screwy, then it could be the control head, and there is not much "you" can do to fix it. Locate the closest service center, and call them, or go to their website.Good luck.

 

[Pat]

AutoHelm 4000 Problems

Blaine,Do you have a Rudder Angle Indicator for your AutoHelm 4000? I have a 2002 356 and the autopilot behaved badly, not tracking well, then I learned about the rudder angle indicator that tells the autopilot when the rudder is otherwise it just chases the selected heading. It vastly improved the steering performance.Thanks,Pat

 

[patrick]

Look to see if the motor turns both ways

You can activate the unit by pushing the button on the control head without engaging the drive unit with the lever. Then you can manually steer the boat a few degrees off the original course. Watch the drive motor and see if it turns appropriately to correct the change. If it turns (corrects) only one direction, the problem is probably in the control head. The power mosfets I mentioned earlier may be open. If it just turns all of the time, that may be shorted mosfets. The control circuit is a bridge type of controller. It is kind of like a bridge rectifier in reverse. There are four transistors which control the motor. They are activated two at a time - one pair is on while the other pair is off. That serves to both activate the motor and the direction - that is controlled by which pair is on. You do not need to actually take the boat out. At the dock, activate the unit with or without engaging the clutch. Then you can push the plus ten button and see if the motor turns to steer that way. Then push the minus ten a couple of times and see if the motor turns the other way.Run some tests and let me know. I am just around the corner if you want to try my control unit. I have an ST4000 - not the plus but I think it should work for troubleshooting. Let me know if you want further help. I have done this before and it is not too hard if you can solder electronics and are not afraid to try it.I saw a control head of unknown condition on eBay a few days ago. You might want to look at that.