420 DA Autopilot calibration question

[BVasily]

My autopilot requires user calibration every time turned on. It will periodically lose calibration during cruising as well. Any advice?

 

[barlow]

In my case the GPS antennae had lost its ability to store its last position. Needed a replacement.

 

[Tenacious]

Make sure you have no metal anywhere near the fluxgate (electronic) compass. If it's clear then you may need a new fluxgate. Can be purchased on Ebay for around $100US or new for a little less than double that at WestMarine or like place. I'm told you cannot splice it and use old cable therefore you will need to run wire from lowest point in boat to helm unit. I've also heard of people compromising and keeping it near the helm, but free/clear of anything metal, electronics, etc., which could interfere with it's operation. Once installed you will in all likelihood have to re-calibrate.

 

[Skybolt]

... I've also heard of people compromising and keeping it near the helm, but free/clear of anything metal, electronics, etc., which could interfere with it's operation. Once installed you will in all likelihood have to re-calibrate.

No good at all. It will never work reliably when you actually "need" it. It needs to be low and isolated to be accurate.

As to the OP's question, I am assuming it is a Raymarine? If so try posting on there forum, but post the exact model and type. I am sure someone there has resolved this issue already. Not sold on the compass causing the re-cal issue as the compass does not store any info in it, it only spits out heading info.

What model do you have?