ST7000 Autopilot

[All U Get]

Hi all,

I've been chasing down the reason for my vintage Autohelm autopilot to stop functioning. I found a 3 amp fuse needing to be replaced, but no luck getting it going. It will turn on and give course headings at the helm but won't turn the wheel. Today I dug into the location of the course computer and unplugged the motor wire leading to the hydraulic pump. (Now you might need a beer to read the next part) I got out the jumper cables and hooked up to the 450 AH house batteries and started up the boat and autopilot. With my wife at the helm and me below with a headset on, I asked her to engage the autopilot then stand away from the wheel. I then tapped the motor leads on the jumper cable clamps and got a spark. My wife said the wheel had turned an inch. I repeated it three times with the same results. Then we shut everything down.

So I'm thinking the computer cannot send current to the pump. Can there be a fuse inside of that black box that I can get into or will Raymarine be able to fix it? BTW first time my wife and I did work on the boat without me getting cut or shocked. (You can finish your beer)

All U Get

 

[Bill Roosa]

Take the volt meter and see it the pump cables are getting juice at the computer terminals. Since it is a DC motor and has to run in two directions the two terminals will be turned on as hot and ground for one direction and ground and hot in the other. ie the volt meter will read positive in one direction and negative in the other.
Good luck

 

[Mickstr]

I would first turn the AP on, select a heading, and using a volt meter check for voltage going to the motor. I have an old Autohelm 4000 (?), that powers a motor on my wheel to turn one way or the other. Turned out my control head was only putting out a few volts, not enough to move the wheel. I had Pop's Circuits replace the voltage regulator in the control head, and so far it's been good about 5 years...

Not sure if that applies to the ST7000 or not...

 

[capta]

If you find that the Autohelm control unit is bad, this might be a good time to move up to a Simrad/Robertson control head. They are almost bullet proof and should power your drive unit without a problem.
Gradually moving away from Raymarine products will simplify your life immensely, and add to the pleasure of your sailing experience.

 

[Lee Hadjiosif]

Before you go replacing your control head or course computer, make sure that it's not the drive that needs replacing. If you call Raymarine support they will give you troubleshooting instructions.
Lee

 

[All U Get]

Take the volt meter and see it the pump cables are getting juice at the computer terminals. Since it is a DC motor and has to run in two directions the two terminals will be turned on as hot and ground for one direction and ground and hot in the other. ie the volt meter will read positive in one direction and negative in the other.
Good luck

Hi Bill,

Tried it several times at the terminals with no volts on the voltmeter. My wife got the error message at the helm "Drive stopped". I did get 13.2 incoming from the batteries.

All U Get