Selfcontained autopilots will have a fluxgate compass inside of them. What kind do you have. My ST4000t (Raymarine) has an external one that I put up in the hanging locker.
Hi,
This is probably to obvious, but have you installed or placed something near your fluxgate compass that would cause it problems? Something like a speaker, motor, etc.
Trust me when I say no statement is too obvious. The answer is no-it just decided one day to go to port. I can get it to go a few degrees to starboard, but that's it.
I guess I'll be climbing inside the hull where no man should have to go-why didn't have boys!!!!!