Autopilot control head reports Current Limit

[Chuck - Raymarine - Moderator]

Autopilot control head reports Current Limit

The reported message is indicating that the autopilot course computer is sensing too much current draw from the drive unit. Causes for this condition may include one or more of the following:

- a problem with the vessel's steering system causing the drive unit to draw excessive current ... check for freedom of movement of the steering system. For example, if the vessel has a mechanical steering system - try to push the rudder quadrant by hand or with the emergency tiller. This will identify if excessive force is needed, possibly steering sheaves seized, steering cable too tight or jammed or maybe rudder stock bearings swollen and jamming the rudder stock. If the steering system is hydraulic, check the oil viscosity is correct, incorrect oil may be too thick or check for dirt in the oil, check valves in the pump may be jammed by foreign particles in the oil.
- rudder limit setting has not been properly configured, causing the drive unit to move the rudder to its stops or mechanical drive unit to be fully extended / retracted.
This value must be configured to 4 degrees less than the maximum rudder angle indicated by the rudder bar display when the rudder is moved fully to port or starboard by the wheel or tiller so that the quadrant or tiller bar is hard against the vessel's mechanical end stops.
- rudder reference transducer / calibration failure causing the autopilot course computer to incorrectly sense the amount of rudder deflection. When this occurs, the drive unit may move the rudder to its stops or mechanical drive unit to be fully extended / retracted. Test the rudder reference transducer and replace/ calibrate the rudder reference transducer.
- a drive unit which is in need of servicing / drive unit failure. Please click here to view a FAQ addressing how to test the drive unit to include its clutch (mechanical drives). Should a problem be identified, then the drive unit should be sent to Raymarine’s Product Repair Center to be bench checked / serviced.
- use of an undersized drive unit and/or course computer for the size of the vessel, steering ram, and/or condition of the seas being operated ... upgrade the drive unit and course computer / ACU to a larger size more suited to the displacement of the vessel or sea conditions anticipated.
- failing autopilot course computer or ACU ... send the autopilot course computer or ACU to ... Raymarine’s Product Repair Center to be bench checked / serviced.


RAYFAQ#