Older Raymarine Autopilot Installation Help Needed

[mannix2]

Hello All,

I am looking for someone to help diagnose and repair my Raymarine Autopilot. Can you help?

Course Computer 400, ST8001 Autopilot Rudder Indicator Problems

I am doing a new installation of a used Raymarine ST8001 Autopilot with a M11805 rudder reference unit (RRU). I have no reason to believe that anything is wrong with the control unit, but when the autopilot is turned on the rudder display indicates the rudder to be in a “hard over” to starboard position. No error message is displayed. Movement of the RRU causes no change.

When the RRU is disconnected, no error messages are displayed.

I have checked the resistance of the RRU and the device checks out to specification. I have switched the Red &Green leads to no avail. (Interestingly, the Commissioning Guide suggests that if the resistance is out of spec, to have the unit repaired. It does not say what to do if the resistance is in spec, i.e., the unit is good.)

Any ideas?

[kcj]

See attached pdfs to test rudder sensor. I got these from ray marine when my ap went off the reservation. Turned out to be a toasted rudder sensor. Replaced sensor, all is well. Ymmv.
Good luck