Autohelm ST 4000 Tiller Pilot and ST50 Steering Compass help!

[Moodyjim]

Got the new old boat to sea for the first time over the weekend but had some issues which I can't seem to resolve. Both the Steering Compass and Tiller Pilot are stuck on 063 degrees and nothing I have tried can change it. Made coming back from Boulogne a bit of a pain!
Any ideas please?
Jim

 

[earlybird]

Prime suspect is the fluxgate compass unit, which separate from the instrument heads. check the wiring to it, and make sure no magnetic material is nearby.