Raymarine Auto Pilot quit working

[TBOT422]

We have a Raymarine Smart Pilot with a linear drive. Yesterday it suddenly stopped working.

• display shows course
  Display shows rudder position
  Press Auto and I hear rudder click (wheel locks in place)
  Pressing any of the +1, +10, -1, -10 keys changes the course on the display but does not activate the drive motor.

Any suggestions as to where to look. The manual implies there is a 25 amp huse to the drive motor, but I dont know where it is.
Thanks for any thoughts.

[smcgauvran]

In my boat, the fuse for the linear drive is in the ACU.

[Captain Kirk]

My course computer is an older Raymarine 150G. It has fuses mounted just above the IO connection board at the bottom of the unit. Included there is a 30 A fuse for the linear drive. I have never had this fuse blow but if there was a issue with linear drive such that it would draw over 30 Amps it should provide the protection.
BTW the DC panel has a 25A breaker on the Autopilot circuit, so it may blow first.

[TBOT422]

We're back in our slip and have done some more research.

Evertyhing on the autopilot seems to work correctly, other than the linear drive does not actuate when pressing any of the +/- keys, so the main breaker on the DC panel does not appear to be the issue.

There does not appear to be a fuse for the linear drive motor in the S1G Controller, but I don't think that is the issue anyway. I tested for voltage at the motor connections on the controller, and never had any voltage at the connections even after I removed the wires to the motor. I have 12V at the power in to the controller, and 12V at the clutch connections when pressing AUTO. No voltage at the motor connections when pressing the +/- keys. So it appears that something is not functioning on the controller board itself. If I could figure out how to remove the circuit board from the housing, and clean it, inspect for visible loose connections, it might be salvagable for awhile. But, after 18 years, maybe it is time to replace all of the electronics.

SmartPilot Connections.jpg (76.4 KiB) Viewed 5597 times