ST7001+ Autopilot Issue

[Team PCBeach]

I have a Raymarine ST7001+ autopilot with S3G Course Computer on our 2003 360 Sundancer. Last week while underway the unit turned off. Cycled the power switch no joy. In my trouble shooting I have gotten to the point where I have power to the wire going unit, but when I connect the wire to the cruise computer the voltage drops to less than one volt. If I pull the fuse at the power input on the cruise computer the voltage jumps up to normal 12V. Any suggestions on what to check next?

 

[ENstig8or]

I am far from an electrical expert, but I'd look at a possible grounding issue.

 

[dtfeld]

Or you have a short in the course computer...what course computer do you have?

 

[Team PCBeach]

Yes, I am thinking short also. I have the Raymarine S3G computer.

 

[dtfeld]

1 V seems odd. Should have approximately 12 (battery voltage) or 0. Corrosion in one of the power leads?

 

[Team PCBeach]

I think there is a short someplace. I ran a new test power lead and get the same response.

Next test will be to disconnect the power lines going to the pump to see if maybe that is the source of the short. If that isn't it, I am going to start leaning towards course computer failure. I just want to confirm that so I can decide if I just want to look for a used course computer or a new autopilot since this one is 15 years old.